\section{\class{wxDb}}\label{wxdb}
-A wxDb instance is a connection to an ODBC data source which may
+A wxDb instance is a connection to an ODBC datasource which may
be opened, closed, and re-opened an unlimited number of times. A
database connection allows function to be performed directly on the
-data source, as well as allowing access to any tables/views defined in
-the data source to which the user has sufficient privileges.
+datasource, as well as allowing access to any tables/views defined in
+the datasource to which the user has sufficient privileges.
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
\wxheading{Include files}
-<wx/version.h>
-<wx/iodbc.h>
-<wx/isqlext.h>
<wx/db.h>
-\latexignore{\rtfignore{\wxheading{Members}}}
-\wxheading{Enumerated types}
+\wxheading{Helper classes and data structures}
-\label{wxdbenumsqllogstate}\docparam{enum {\bf wxDbSqlLogState}}{sqlLogOFF, sqlLogON}
+The following classes and structs are defined in db.cpp/.h for use with the wxDb class.
-{\it enum {\bf wxDBMS}}
+\begin{itemize}\itemsep=0pt
+\item \helpref{wxDbColFor}{wxdbcolfor}
+\item \helpref{wxDbColInf}{wxdbcolinf}
+\item \helpref{wxDbTableInf}{wxdbtableinf}
+\item \helpref{wxDbInf}{wxdbinf}
+\end{itemize}
-These are the databases currently tested and working with these ODBC classes.
-A call to \helpref{wxDb::Dbms}{wxdbdbms} will return one of these enumerated values listed below.
+\wxheading{Constants}
+
+NOTE: In a future release, all ODBC class constants will be prefaced with 'wx'.
\begin{verbatim}
- dbmsUNIDENTIFIED,
- dbmsORACLE,
- dbmsSYBASE_ASA, // Adaptive Server Anywhere
- dbmsSYBASE_ASE, // Adaptive Server Enterprise
- dbmsMS_SQL_SERVER,
- dbmsMY_SQL,
- dbmsPOSTGRES,
- dbmsACCESS,
- dbmsDBASE,
- dbmsINFORMIX
+ wxDB_PATH_MAX Maximum path length allowed to be passed to
+ the ODBC driver to indicate where the data
+ file(s) are located.
+
+ DB_MAX_COLUMN_NAME_LEN Maximum supported length for the name of a
+ column
+
+ DB_MAX_ERROR_HISTORY Maximum number of error messages retained in
+ the queue before being overwritten by new
+ errors.
+
+ DB_MAX_ERROR_MSG_LEN Maximum supported length of an error message
+ returned by the ODBC classes
+
+ DB_MAX_STATEMENT_LEN Maximum supported length for a complete SQL
+ statement to be passed to the ODBC driver
+
+ DB_MAX_TABLE_NAME_LEN Maximum supported length for the name of a
+ table
+
+ DB_MAX_WHERE_CLAUSE_LEN Maximum supported WHERE clause length that
+ can be passed to the ODBC driver
+
+ DB_TYPE_NAME_LEN Maximum length of the name of a column's
+ data type
\end{verbatim}
-See the remarks in \helpref{wxDb::Dbms}{wxdbdbms} for exceptions/issues with
-each of these database engines.
+\subsection{Enumerated types}\label{wxdbenumeratedtypes}
+
+\wxheading{Enumerated types}
+
+\docparam{enum {\bf wxDbSqlLogState}}{sqlLogOFF, sqlLogON}
+
+{\it enum {\bf wxDBMS}}
+These are the databases currently tested and working with the ODBC classes. A call to \helpref{wxDb::Dbms}{wxdbdbms} will return one of these enumerated values listed below.
+
+\begin{itemize}\itemsep=0pt
+\item DB2
+\item DBase (IV, V)**
+\item Firebird
+\item INFORMIX
+\item Interbase
+\item MS SQL Server (v7 - minimal testing)
+\item MS Access (97, 2000, 2002, and 2003)
+\item MySQL (2.x and 3.5 - use the 2.5x drivers though)
+\item Oracle (v7, v8, v8i)
+\item Pervasive SQL
+\item PostgreSQL
+\item Sybase (ASA and ASE)
+\item XBase Sequiter
+\item VIRTUOSO
+\end{itemize}
+
+See the remarks in \helpref{wxDb::Dbms}{wxdbdbms} for exceptions/issues with each of these database engines.
\wxheading{Public member variables}
-\docparam{SWORD {\bf wxDb::cbErrorMsg}}{This member variable is populated as a result of
-calling \helpref{wxDb::GetNextError}{wxdbgetnexterror}. Contains the count of bytes in the wxDb::errorMsg string.}
+\docparam{SWORD {\bf wxDb::cbErrorMsg}}{This member variable is populated as a result of calling \helpref{wxDb::GetNextError}{wxdbgetnexterror}. Contains the count of bytes in the wxDb::errorMsg string.}
-\label{wxdbdbstatus}\docparam{int {\bf wxDb::DB_STATUS}}{The last ODBC error that occured on this data connection. Possible codes are:}
+\docparam{int {\bf wxDb::DB\_STATUS}}{The last ODBC error/status that occurred on this data connection. Possible codes are:}
\begin{verbatim}
DB_ERR_GENERAL_WARNING // SqlState = '01000'
DB_ERR_TIMEOUT_EXPIRED // SqlState = 'S1T00'
\end{verbatim}
-
-\docparam{struct {\bf wxDb::dbInf}}{This structure is internal to the wxDb class and contains
-details of the ODBC datasource that the current instance of the wxDb is connected to
-in its members. When the data source is opened, all of the information contained in
-the dbInf structure is queried from the data source. This information is used almost
-exclusively within the ODBC class library. Where there is a need for this information
-outside of the class library a member function such as wxTable::IsCursorClosedOnCommit()
-has been added for ease of use.}
+\docparam{struct {\bf wxDb::dbInf}}{This structure is internal to the
+wxDb class and contains details of the ODBC datasource that the current
+instance of the wxDb is connected to in its members. When the datasource
+is opened, all of the information contained in the dbInf structure is
+queried from the datasource. This information is used almost exclusively
+within the ODBC class library. Where there may be a need for particular
+portions of this information outside of the class library, member
+functions (e.g.
+\helpref{wxDbTable::IsCursorClosedOnCommit}{wxdbtableiscursorclosedoncommit})
+have been added for ease of use.}
\begin{verbatim}
- char dbmsName[40] - Name of the dbms product
- char dbmsVer[64] - Version # of the dbms product
- char driverName[40] - Driver name
- char odbcVer[60] - ODBC version of the driver
- char drvMgrOdbcVer[60] - ODBC version of the driver manager
- char driverVer[60] - Driver version
- char serverName[80] - Server Name, typically a connect string
- char databaseName[128] - Database filename
- char outerJoins[2] - Does datasource support outer joins
- char procedureSupport[2] - Does datasource support stored procedures
- UWORD maxConnections - Maximum # of connections datasource supports
+ wxChar dbmsName[40] - Name of the dbms product
+ wxChar dbmsVer[64] - Version # of the dbms product
+ wxChar driverName[40] - Driver name
+ wxChar odbcVer[60] - ODBC version of the driver
+ wxChar drvMgrOdbcVer[60] - ODBC version of the driver manager
+ wxChar driverVer[60] - Driver version
+ wxChar serverName[80] - Server Name, typically a connect string
+ wxChar databaseName[128] - Database filename
+ wxChar outerJoins[2] - Does datasource support outer joins
+ wxChar procedureSupport[2] - Does datasource support stored
+ procedures
+ UWORD maxConnections - Maximum # of connections datasource
+ supports
UWORD maxStmts - Maximum # of HSTMTs per HDBC
UWORD apiConfLvl - ODBC API conformance level
UWORD cliConfLvl - Is datasource SAG compliant
UWORD sqlConfLvl - SQL conformance level
UWORD cursorCommitBehavior - How cursors are affected on db commit
- UWORD cursorRollbackBehavior - How cursors are affected on db rollback
- UWORD supportNotNullClause - Does datasource support NOT NULL clause
- char supportIEF[2] - Integrity Enhancement Facility (Ref. Integrity)
- UDWORD txnIsolation - Transaction isolation level supported by driver
- UDWORD txnIsolationOptions - Transaction isolation level options available
+ UWORD cursorRollbackBehavior - How cursors are affected on db
+ rollback
+ UWORD supportNotNullClause - Does datasource support NOT NULL
+ clause
+ wxChar supportIEF[2] - Integrity Enhancement Facility (Ref.
+ Integrity)
+ UDWORD txnIsolation - Transaction isolation level supported by
+ driver
+ UDWORD txnIsolationOptions - Transaction isolation level options
+ available
UDWORD fetchDirections - Fetch directions supported
UDWORD lockTypes - Lock types supported in SQLSetPos
- UDWORD posOperations - Position operations supported in SQLSetPos
+ UDWORD posOperations - Position operations supported in
+ SQLSetPos
UDWORD posStmts - Position statements supported
- UDWORD scrollConcurrency - Scrollable cursor concurrency options supported
+ UDWORD scrollConcurrency - Scrollable cursor concurrency options
+ supported
UDWORD scrollOptions - Scrollable cursor options supported
- UDWORD staticSensitivity - Can additions/deletions/updates be detected
- UWORD txnCapable - Indicates if datasource supports transactions
- UDWORD loginTimeout - Number seconds to wait for a login request
+ UDWORD staticSensitivity - Can additions/deletions/updates be
+ detected
+ UWORD txnCapable - Indicates if datasource supports
+ transactions
+ UDWORD loginTimeout - Number seconds to wait for a login
+ request
\end{verbatim}
-\docparam{char {\bf wxDb::errorList}[DB_MAX_ERROR_HISTORY][DB_MAX_ERROR_MSG_LEN]}{The last n ODBC errors that have occured on this database connection.}
+\docparam{wxChar {\bf wxDb::errorList}[DB\_MAX\_ERROR\_HISTORY][DB\_MAX\_ERROR\_MSG\_LEN]}{The last n ODBC errors that have occurred on this database connection.}
-\docparam{char {\bf wxDb::errorMsg}[SQL_MAX_MESSAGE_LENGTH]}{This member variable is populated as a result of calling \helpref{wxDb::GetNextError}{wxdbgetnexterror}. It contains the ODBC error message text.}
+\docparam{wxChar {\bf wxDb::errorMsg}[SQL\_MAX\_MESSAGE\_LENGTH]}{This member variable is populated as a result of calling \helpref{wxDb::GetNextError}{wxdbgetnexterror}. It contains the ODBC error message text.}
-\docparam{SDWORD {\bf wxDb::nativeError}}{Set by wxDb::DispAllErrors, wxDb::GetNextError, and wxDb::DispNextError. It contains the datasource-specific error code returned by the datasource to the ODBC driver. Used for reporting ODBC errors.}
+\docparam{SDWORD {\bf wxDb::nativeError}}{Set by wxDb::DispAllErrors,
+wxDb::GetNextError, and wxDb::DispNextError. It contains the
+datasource-specific error code returned by the datasource to the ODBC driver.
+Used for reporting ODBC errors.}
-\docparam{wxChar {\bf wxDb::sqlState}[20]}{Set by wxDb::TranslateSqlState(). Indicates the error state after a failed ODBC operation. Used for reporting ODBC errors.}
+\docparam{wxChar {\bf wxDb::sqlState}[20]}{Set by wxDb::TranslateSqlState().
+Indicates the error state after a failed ODBC operation. Used for reporting
+ODBC errors.}
-\docparam{unsigned int {\bf nTables}}{Number of wxDbTable objects connected to this wxDb instance. {\bf FOR INTERNAL USE ONLY} by wxDbTable!!!}
+\wxheading{Remarks}
-{\it wxDbSqlTypeInfo {\bf typeInfVarchar}}
+Default cursor scrolling is defined by wxODBC\_FWD\_ONLY\_CURSORS in setup.h
+when the wxWidgets library is built. This behavior can be overridden when
+an instance of a wxDb is created (see \helpref{wxDb constructor}{wxdbctor}).
+Default setting of this value true, as not all databases/drivers support
+both types of cursors.
-{\it wxDbSqlTypeInfo {\bf typeInfInteger}}
+\wxheading{See also}
-{\it wxDbSqlTypeInfo {\bf typeInfFloat}}
+\helpref{wxDbColFor}{wxdbcolfor}, \helpref{wxDbColInf}{wxdbcolinf},
+\helpref{wxDbTable}{wxdbtable}, \helpref{wxDbTableInf}{wxdbtableinf},
+\helpref{wxDbInf}{wxdbinf}
-{\it wxDbSqlTypeInfo {\bf typeInfDate}}
+\subsection{Associated non-class functions}\label{wxdbfunctions}
-\begin{indented}{1cm}
-The four wxDbSqlTypeInfo member variables listed above contain information about logical data types VARCHAR, INTEGER, FLOAT and DATE.
+The following functions are used in conjunction with the wxDb class.
-This information is obtained from the ODBC driver by use of the ::SQLGetTypeInfo() function. The key piece of information is the type name the datasource uses for each logical data type. e.g. VARCHAR; Oracle calls it VARCHAR2.
-\end{indented}
+\func{void}{wxDbCloseConnections}{\void}
\wxheading{Remarks}
-Default cursor scrolling is defined by wxODBC_FWD_ONLY_CURSORS in setup.h
-when the wxWindows library is built. This behavior can be overridden when
-an instance of a wxDb is created (see \helpref{wxDb constructor}{wxdbconstr}
+Closes all cached connections that have been made through use of the
+\helpref{wxDbGetConnection}{wxdbfunctions} function.
-\wxheading{See also}
+NOTE: These connections are closed regardless of whether they are in use
+or not. This function should only be called after the program has
+finished using the connections and all wxDbTable instances that use any of
+the connections have been closed.
+
+This function performs a \helpref{wxDb::CommitTrans}{wxdbcommittrans}
+on the connection before closing it to commit any changes that are still
+pending, as well as to avoid any function sequence errors upon closing
+each connection.
+
+
+\func{int }{wxDbConnectionsInUse}{\void}
+
+\wxheading{Remarks}
+
+Returns a count of how many database connections are currently free ( not
+being used) that have been cached through use of the \helpref{wxDbGetConnection}{wxdbfunctions}
+function.
+
+
+\func{bool}{wxDbFreeConnection}{\param{wxDb *}{pDb}}
+
+\wxheading{Remarks}
+
+Searches the list of cached database connections connection for one matching
+the passed in wxDb instance. If found, that cached connection is freed.
-\helpref{wxDbColFor}{wxdbcolfor}, \helpref{wxDbColInf}{wxdbcolinf}, \helpref{wxDbTable}{wxdbtable}, \helpref{wxDbTableInf}{wxdbtableinf}, \helpref{wxDbInf}{wxdbinf}
+Freeing a connection means that it is marked as available (free) in the
+cache of connections, so that a call to \helpref{wxDbGetConnection}{wxdbfunctions}
+is able to return a pointer to the wxDb instance for use. Freeing a
+connection does NOT close the connection, it only makes the connection
+available again.
+\func{wxDb *}{wxDbGetConnection}{\param{wxDbConnectInf *}{pDbConfig},
+\param{bool }{FwdOnlyCursors=(bool)wxODBC\_FWD\_ONLY\_CURSORS}}
-\membersection{wxDb::wxDb}\label{wxdbconstr}
+\wxheading{Remarks}
+
+This function is used to request a "new" wxDb instance for use by the program.
+The wxDb instance returned is also opened (see \helpref{wxDb::Open}{wxdbopen}).
+
+This function (along with wxDbFreeConnection() and wxDbCloseConnection())
+maintain a cache of wxDb instances for user/re-use by a program. When a
+program needs a wxDb instance, it may call this function to obtain a wxDb
+instance. If there is a wxDb instance in the cache that is currently unused
+that matches the connection requirements specified in {\it'pDbConfig'} then
+that cached connection is marked as no longer being free, and a pointer to
+the wxDb instance is returned.
+
+If there are no connections available in the cache that meet the requirements
+given in {\it'pDbConfig'}, then a new wxDb instance is created to connect
+to the datasource specified in {\it'pDbConfig'} using the userID and password
+given in {\it'pDbConfig'}.
+
+NOTE: The caching routine also uses the \helpref{wxDb::Open}{wxdbopen}
+connection datatype copying code. If the call to wxDbGetConnection()
+requests a connection to a datasource, and there is not one available in the
+cache, a new connection is created. But when the connection is opened,
+instead of polling the datasource over again for its datatypes, if a
+connection to the same datasource (using the same userID/password) has already
+been done previously, the new connection skips querying the datasource for
+its datatypes, and uses the same datatypes determined previously by the
+other connection(s) for that same datasource. This cuts down greatly on
+network traffic, database load, and connection creation time.
+
+When the program is done using a connection created through a call to
+wxDbGetConnection(), the program should call wxDbFreeConnection() to release
+the wxDb instance back to the cache. DO NOT DELETE THE wxDb INSTANCE!
+Deleting the wxDb instance returned can cause a crash/memory corruption
+later in the program when the cache is cleaned up.
+
+When exiting the program, call wxDbCloseConnections() to close all the
+cached connections created by calls to wxDbGetConnection().
+
+
+\func{const wxChar *}{wxDbLogExtendedErrorMsg}{\param{const wxChar *}{userText}, \param{wxDb *}{pDb}, \param{wxChar *}{ErrFile}, \param{int }{ErrLine}}
+
+Writes a message to the wxLog window (stdout usually) when an internal
+error situation occurs.
+
+\func{bool}{wxDbSqlLog}{\param{wxDbSqlLogState }{state}, \param{const wxString \&}{filename = SQL\_LOG\_FILENAME}}
+
+\wxheading{Remarks}
+
+This function sets the sql log state for all open wxDb objects
+
+\func{bool}{wxDbGetDataSource}{\param{HENV }{henv}, \param{wxChar *}{Dsn}, \param{SWORD }{DsnMax}, \param{wxChar *}{DsDesc}, \param{SWORD }{DsDescMax}, \param{UWORD }{direction = SQL\_FETCH\_NEXT}}
+
+\wxheading{Remarks}
+
+This routine queries the ODBC driver manager for a list of available
+datasources. Repeatedly call this function to obtain all the datasources
+available through the ODBC driver manager on the current workstation.
+
+\begin{verbatim}
+ wxArrayString strArray;
+
+ while (wxDbGetDataSource(DbConnectInf.GetHenv(), Dsn, SQL_MAX_DSN_LENGTH+1, DsDesc, 255))
+ strArray.Add(Dsn);
+\end{verbatim}
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDb::wxDb}\label{wxdbctor}
\func{}{wxDb}{\void}
Default constructor.
-\func{}{wxDb}{\param{HENV\& }{aHenv}}
+\func{}{wxDb}{\param{const HENV \&}{aHenv}, \param{bool }{FwdOnlyCursors=(bool)wxODBC\_FWD\_ONLY\_CURSORS}}
-Constructor, used to create an ODBC connection to a data source.
+Constructor, used to create an ODBC connection to a datasource.
\wxheading{Parameters}
-\docparam{aHenv}{Environment handle defined in iODBC}
+\docparam{aHenv}{Environment handle used for this connection. See
+\helpref{wxDConnectInf::AllocHenv}{wxdbconnectinfallochenv}}
+
+\docparam{FwdOnlyCursors}{Will cursors created for use with this datasource
+connection only allow forward scrolling cursors.}
\wxheading{Remarks}
be created and opened before any database activity can occur.
\wxheading{Example}
+
\begin{verbatim}
wxDbConnectInf ConnectInf;
....Set values for member variables of ConnectInf here
- wxDb sampleDB(ConnectInf.Henv);
- if (!sampleDB.Open(ConnectInf.Dsn, ConnectInf.Uid, ConnectInf.AuthStr))
+ wxDb sampleDB(ConnectInf.GetHenv());
+ if (!sampleDB.Open(ConnectInf.GetDsn(), ConnectInf.GetUserID(),
+ ConnectInf.GetPassword()))
{
- // Error opening data source
+ // Error opening datasource
}
\end{verbatim}
+\wxheading{See also}
+
+\helpref{wxDbGetConnection}{wxdbfunctions}
\membersection{wxDb::Catalog}\label{wxdbcatalog}
-\func{bool}{Catalog}{\param{char *}{ userID}, \param{char *}{fileName = SQL_CATALOG_FILENAME}}
+\func{bool}{Catalog}{\param{wxChar *}{ userID}, \param{const wxString \&}{fileName =
+SQL\_CATALOG\_FILENAME}}
-Allows a data "dictionary" of the data source to be created, dumping pertinent information about all data tables to which the user specified in userID has access.
+Allows a data "dictionary" of the datasource to be created, dumping pertinent
+information about all data tables to which the user specified in userID has
+access.
\wxheading{Parameters}
-\docparam{userID}{Database user name to use in accessing the database. All tables to which this user has rights will be evaluated in the catalog.}
+\docparam{userID}{Database user name to use in accessing the database. All
+tables to which this user has rights will be evaluated in the catalog.}
-\docparam{fileName}{OPTIONAL argument. Name of the text file to create and write the DB catalog to.}
+\docparam{fileName}{{\it OPTIONAL}. Name of the text file to create and write
+the DB catalog to. Default is SQL\_CATALOG\_FILENAME.}
\wxheading{Return value}
-Returns TRUE if the catalog request was successful, of FALSE if there was some reason the catalog could not be generated
+Returns true if the catalog request was successful, or false if there was some
+reason that the catalog could not be generated.
\wxheading{Example}
+
\begin{verbatim}
============== ============== ================ ========= =======
TABLE NAME COLUMN NAME DATA TYPE PRECISION LENGTH
\wxheading{Remarks}
-At the end of your program, when you have finished all of your database work, you must close the ODBC connection to the data source. There are actually four steps involved in doing this as illustrated in the example.
+At the end of your program, when you have finished all of your database work,
+you must close the ODBC connection to the datasource. There are actually
+four steps involved in doing this as illustrated in the example.
-Any wxTable instances which use this connection must be deleted before closing the database connection.
+Any wxDbTable instances which use this connection must be deleted before
+closing the database connection.
\wxheading{Example}
+
\begin{verbatim}
- // Commit any open transactions on the data source
+ // Commit any open transactions on the datasource
sampleDB.CommitTrans();
- // Delete any remaining wxTable objects allocated with new
+ // Delete any remaining wxDbTable objects allocated with new
delete parts;
// Close the wxDb connection when finished with it
sampleDB.Close();
-
- // Free Environment Handle that ODBC uses
- if (SQLFreeEnv(Db.Henv) != SQL_SUCCESS)
- {
- // Error freeing environment handle
- }
\end{verbatim}
\func{bool}{CommitTrans}{\void}
-Permanently "commits" changes (insertions/deletions/updates) to the database.
+Permanently "commits" changes (insertions/deletions/updates) to the database.
\wxheading{Return value}
-Returns TRUE if the commit was successful, or FALSE if the commit failed.
+Returns true if the commit was successful, or false if the commit failed.
\wxheading{Remarks}
-Transactions begin implicitly as soon as you make a change to the database. At any time thereafter, you can save your work to the database ("Commit") or roll back all of your changes ("Rollback"). Calling this member function commits all open transactions on this ODBC connection.
+Transactions begin implicitly as soon as you make a change to the database
+with an insert/update/delete, or any other direct SQL command that performs
+one of these operations against the datasource.
+At any time thereafter, to save the changes to disk permanently, "commit"
+them by calling this function.
+
+Calling this member function commits ALL open transactions on this ODBC
+connection. For example, if three different wxDbTable instances used the
+same connection to the datasource, committing changes made on one of those
+wxDbTable instances commits any pending transactions on all three wxDbTable
+instances.
+
+Until a call to wxDb::CommitTrans() is made, no other user or cursor is able
+to see any changes made to the row(s) that have been inserted/modified/deleted.
+
\wxheading{Special Note : {\it Cursors} }
-\normalbox{It is important to understand that different database/ODBC driver combinations handle
-transactions differently. One thing in particular that you must pay attention to is
-cursors, in regard to transactions. Cursors are what allow you to scroll through
-records forward and backward and to manipulate records as you scroll through them.
-When you issue a query, a cursor is created behind the scenes. The cursor keeps track
-of the query and keeps track of the current record pointer. After you commit or
-rollback a transaction, the cursor may be closed automatically. This means you must
-requery the data source before you can perform any additional work against the wxTable
-object. This is only necessary however if the data source closes the cursor after a
-commit or rollback. Use the wxTable::IsCursorClosedOnCommit() member function to
-determine the data source's transaction behavior. Note, it would be very inefficient
-to just assume the data source closes the cursor and always requery. This could put
-a significant, unnecessary load on data sources that leave the cursors open after a
-transaction.}
+\normalbox{It is important to understand that different database/ODBC driver
+combinations handle transactions differently. One thing in particular that
+you must pay attention to is cursors, in regard to transactions. Cursors are
+what allow you to scroll through records forward and backward and to
+manipulate records as you scroll through them. When you issue a query, a
+cursor is created behind the scenes. The cursor keeps track of the query and
+keeps track of the current record pointer. After you commit or rollback a
+transaction, the cursor may be closed automatically. This is database
+dependent, and with some databases this behavior can be controlled through
+management functions. This means you would need to requery the datasource
+before you can perform any additional work using this cursor. This is only
+necessary however if the datasource closes the cursor after a commit or
+rollback. Use the
+\helpref{wxDbTable::IsCursorClosedOnCommit}{wxdbtableiscursorclosedoncommit}
+member function to determine the datasource's transaction behavior. Note, in
+many situations it is very inefficient to assume the cursor is closed and
+always requery. This could put a significant, unnecessary load on datasources
+that leave the cursors open after a transaction.}
\membersection{wxDb::CreateView}\label{wxdbcreateviews}
-\func{bool}{CreateView}{\param{char *}{ viewName}, \param{char *}{ colList}, \param{char *}{pSqlStmt}}
+\func{bool}{CreateView}{\param{const wxString \&}{ viewName},
+\param{const wxString \&}{ colList}, \param{const wxString \&}{pSqlStmt}}
-Creates a SQL VIEW.
+Creates a SQL VIEW of one or more tables in a single datasource. Note that
+this function will only work against databases which support views (currently
+only Oracle as of November 21 2000).
\wxheading{Parameters}
-\docparam{viewName}{The name of the view. e.g. PARTS_V}
-\docparam{colList}{{\it OPTIONAL} Pass in a comma delimited list of column names if you
-wish to explicitly name each column in the result set. If not desired, pass in an
-empty string.}
-\docparam{pSqlStmt}{Pointer to the select statement portion of the CREATE VIEW statement.
-Must be a complete, valid SQL SELECT statement.}
+\docparam{viewName}{The name of the view. e.g. PARTS\_V}
+
+\docparam{colList}{{\it OPTIONAL} Pass in a comma delimited list of column
+names if you wish to explicitly name each column in the result set. If not
+desired, pass in an empty string and the column names from the associated
+table(s) will be used.}
+
+\docparam{pSqlStmt}{Pointer to the select statement portion of the CREATE
+VIEW statement. Must be a complete, valid SQL SELECT statement.}
\wxheading{Remarks}
-A 'view' is a logical table that derives columns from one or more other tables or views. Once the view is created, it can be queried exactly like any other table in the database.
+A 'view' is a logical table that derives columns from one or more other
+tables or views. Once the view is created, it can be queried exactly like
+any other table in the database.
-NOTE: Views are not available with all datasources. Oracle is one example of a datasouce which does support views.
+NOTE: Views are not available with all datasources. Oracle is one example
+of a datasource which does support views.
\wxheading{Example}
+
\begin{verbatim}
// Incomplete code sample
- db.CreateView("PARTS_SD1", "PN, PD, QTY",
- "SELECT PART_NO, PART_DESC, QTY_ON_HAND * 1.1 FROM PARTS WHERE STORAGE_DEVICE = 1");
+ db.CreateView("PARTS_SD1", "PN, PD, QTY",
+ "SELECT PART_NUM, PART_DESC, QTY_ON_HAND * 1.1 FROM PARTS \
+ WHERE STORAGE_DEVICE = 1");
// PARTS_SD1 can now be queried just as if it were a data table.
// e.g. SELECT PN, PD, QTY FROM PARTS_SD1
\end{verbatim}
+\membersection{wxDb::Dbms}\label{wxdbdbms}
+
+\func{wxDBMS }{Dbms}{\void}
+
+\wxheading{Remarks}
+
+The return value will be of the enumerated type wxDBMS. This enumerated
+type contains a list of all the currently tested and supported databases.
+
+Additional databases may work with these classes, but the databases
+returned by this function have been tested and confirmed to work with
+these ODBC classes.
+
+Possible values returned by this function can be viewed in the
+\helpref{Enumerated types}{wxdbenumeratedtypes} section of wxDb.
+
+There are known issues with conformance to the ODBC standards with several
+datasources supported by the wxWidgets ODBC classes. Please see the overview
+for specific details on which datasource have which issues.
+
+\wxheading{Return value}
+
+The return value will indicate which of the supported datasources is
+currently connected to by this connection. In the event that the
+datasource is not recognized, a value of 'dbmsUNIDENTIFIED' is returned.
+
+
\membersection{wxDb::DispAllErrors}\label{wxdbdispallerrors}
-\func{bool}{DispAllErrors}{\param{HENV}{ aHenv}, {\param}{HDBC}{ aHdbc = SQL_NULL_HDBC}, {\param}{HSTMT}{ aHstmt = SQL_NULL_HSTMT}}
+\func{bool}{DispAllErrors}{\param{HENV}{ aHenv}, \param{HDBC}{ aHdbc = SQL\_NULL\_HDBC}, \param{HSTMT}{ aHstmt = SQL\_NULL\_HSTMT}}
-Logs all database errors that occurred as a result of the last executed database command. This logging also includes debug logging when compiled in debug mode via \helpref{wxLogDebug}{wxlogdebug}. If logging is turned on via \helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging}, then an entry is also logged to the defined log file.
+Used to log all database errors that occurred as a result of an executed
+database command. This logging is automatic and also includes debug logging
+when compiled in debug mode via \helpref{wxLogDebug}{wxlogdebug}. If logging
+is turned on via \helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging}, then an
+entry is also logged to the defined log file.
\wxheading{Parameters}
-\docparam{aHenv}{A handle to the ODBC environment.}
-\docparam{aHdbc}{A handle to the ODBC connection. Pass this in if the ODBC function call that
-erred out required a hdbc or hstmt argument.}
-\docparam{AHstmt}{A handle to the ODBC statement being executed against. Pass this in if the
-ODBC function call that erred out required a hstmt argument.}
+\docparam{aHenv}{Handle to the ODBC environment.}
+
+\docparam{aHdbc}{Handle to the ODBC connection. Pass this in if the ODBC
+function call that erred required a hdbc or hstmt argument.}
+
+\docparam{aHstmt}{Handle to the ODBC statement being executed against. Pass
+this in if the ODBC function call that failed required a hstmt argument.}
\wxheading{Remarks}
-This member function will display all of the ODBC error messages for the last ODBC function call that was made. Normally used internally within the ODBC class library. Would be used externally if calling ODBC functions directly (i.e. SQLFreeEnv()).
+This member function will log all of the ODBC error messages for the last
+ODBC function call that was made. This function is normally used internally
+within the ODBC class library, but can be used programmatically after calling
+ODBC functions directly (i.e. SQLFreeEnv()).
+
+\wxheading{Return value}
+
+The function always returns false, so a call to this function can be made
+in the return statement of a code block in the event of a failure to
+perform an action (see the example below).
\wxheading{See also}
-\helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging}, \helpref{wxDbSqlLog}{wxdbsqllog}
+\helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging}, wxDbSqlLog
\wxheading{Example}
+
\begin{verbatim}
if (SQLExecDirect(hstmt, (UCHAR FAR *) pSqlStmt, SQL_NTS) != SQL_SUCCESS)
// Display all ODBC errors for this stmt
return(db.DispAllErrors(db.henv, db.hdbc, hstmt));
\end{verbatim}
-
\membersection{wxDb::DispNextError}\label{wxdbdispnexterror}
\func{void}{DispNextError}{\void}
\wxheading{Remarks}
This function is normally used internally within the ODBC class library.
-It could be used externally if calling ODBC functions directly. This
+It could be used programmatically after calling ODBC functions directly. This
function works in conjunction with \helpref{wxDb::GetNextError}{wxdbgetnexterror} when errors (or
sometimes informational messages) returned from ODBC need to be analyzed
rather than simply displaying them as an error. GetNextError() retrieves
one in context and displaying the ones you choose.
\wxheading{Example}
+
\begin{verbatim}
// Drop the table before attempting to create it
sprintf(sqlStmt, "DROP TABLE %s", tableName);
// Check for sqlState = S0002, "Table or view not found".
// Ignore this error, bomb out on any other error.
pDb->GetNextError(henv, hdbc, hstmt);
- if (strcmp(pDb->sqlState, "S0002"))
+ if (wxStrcmp(pDb->sqlState, "S0002"))
{
pDb->DispNextError(); // Displayed error retrieved
pDb->DispAllErrors(henv, hdbc, hstmt); // Display all other errors, if any
pDb->RollbackTrans(); // Rollback the transaction
CloseCursor(); // Close the cursor
- return(FALSE); // Return Failure
+ return(false); // Return Failure
}
}
\end{verbatim}
\membersection{wxDb::DropView}\label{wxdbdropview}
-\func{bool}{DropView}{\param{const char *}{viewName}}
+\func{bool}{DropView}{\param{const wxString \&}{viewName}}
Drops the data table view named in 'viewName'.
\wxheading{Remarks}
-If the view does not exist, this function will return TRUE. Note that views are not supported with all data soruces.
+If the view does not exist, this function will return true. Note that views are not supported with all datasources.
+
+\membersection{wxDb::EscapeSqlChars}\label{wxdbescapesqlchars}
+
+\func{wxString}{EscapeSqlChars}{\param{const wxString\& }{value}}
+
+This function is used internally by wxWidgets while building SQL statements.
+It has been provided to help users who wish to explicity construct SQL
+statements to be sent to the server. The function takes the value passed and
+returns it with any special characters escaped. Which characters are
+considered special depends on what type of datasource the object is connected
+to. For example, most database servers use a backslash as the escape
+character; if the value passed contains a backlash it will be replaced with a
+double backslash before it is passed to the server. This function can be used
+to avoid passing statements with syntax errors to the server as well as prevent
+SQL injection attacks.
+\wxheading{Parameters}
+
+\docparam{value}{The value to be escaped.}
\membersection{wxDb::ExecSql}\label{wxdbexecsql}
-\func{bool}{ExecSql}{\param{char *}{pSqlStmt}}
+\func{bool}{ExecSql}{\param{const wxString \&}{pSqlStmt}}
+
+\func{bool}{ExecSql}{\param{const wxString \&}{pSqlStmt}, \param{wxDbColInf **}{columns}, \param{short \&}{numcols}}
Allows a native SQL command to be executed directly against the datasource. In addition to being able to run any standard SQL command, use of this function allows a user to (potentially) utilize features specific to the datasource they are connected to that may not be available through ODBC. The ODBC driver will pass the specified command directly to the datasource.
+To get column amount and column names or other information about returned columns, pass {\it 'columns'} and {\it 'numcols'} parameters to the function also.
+
\wxheading{Parameters}
\docparam{pSqlStmt}{Pointer to the SQL statement to be executed.}
+\docparam{columns}{On success, this function will set this pointer to point to array of \helpref{wxDbColInf}{wxdbcolinf} objects, holding information about columns returned by the query. You need to call delete[] for the pointer you pass here after you don't use it anymore to prevent memory leak.}
+
+\docparam{numcols}{Reference to variable where amount of objects in {\it 'columns'}-parameter will be set.}
+
\wxheading{Remarks}
This member extends the wxDb class and allows you to build and execute ANY VALID
-SQL statement against the data source. This allows you to extend the class
-library by being able to issue any SQL statement that the data source is capable
+SQL statement against the datasource. This allows you to extend the class
+library by being able to issue any SQL statement that the datasource is capable
of processing.
\wxheading{See also}
\helpref{wxDb::GetData}{wxdbgetdata}, \helpref{wxDb::GetNext}{wxdbgetnext}
-
\membersection{wxDb::FwdOnlyCursors}\label{wxdbfwdonlycursors}
-\func{bool}{FwdOnlyCursors}{\void}
-
-Indicates whether this connection to the datasource only allows forward scrolling cursors or not. This state is set at connection creation time.
+\func{bool}{IsFwdOnlyCursors}{\void}
-\wxheading{See also}
+Older form (pre-2.3/2.4 of wxWidgets) of the
+\helpref{wxDb::IsFwdOnlyCursors}{wxdbisfwdonlycursors}. This method is
+provided for backward compatibility only. The method
+\helpref{wxDb::IsFwdOnlyCursors}{wxdbisfwdonlycursors} should be
+used in place of this method.
-\helpref{wxDb::wxDb}{wxdbconstruct}, \helpref{wxDbGetConnection}{wxdbgetconnection}
+\func{wxDbInf *}{GetCatalog}{\param{const wxChar *}{userID}}
\membersection{wxDb::GetCatalog}\label{wxdbgetcatalog}
-\func{wxDbInf *}{GetCatalog}{\param{char *}{userID}}
+\func{wxDbInf *}{GetCatalog}{\param{const wxChar *}{userID}}
-Returns a wxDbInf pointer that points to the catalog(data source) name, schema, number of tables accessible to the current user, and a wxDbTableInf pointer to all data pertaining to all tables in the users catalog.
+Returns a \helpref{wxDbInf}{wxdbinf} pointer that points to the catalog
+(datasource) name, schema, number of tables accessible to the current user,
+and a wxDbTableInf pointer to all data pertaining to all tables in the users
+catalog.
\wxheading{Parameters}
-\docparam{userID}{Owner of the table. Specify a userID when the datasource you are connected
-to allows multiple unique tables with the same name to be owned by different users. {\it userID}
-is evaluated as follows:}
+\docparam{userID}{Owner/Schema of the table. Specify a userID when the datasource you are connected to allows multiple unique tables with the same name to be owned by different users. {\it userID} is evaluated as follows:}
\begin{verbatim}
userID == NULL ... UserID is ignored (DEFAULT)
\wxheading{Remarks}
-The returned catalog will only contain catalog entries for tables to which the user specified in 'userID' has sufficient privileges. If no user is specified (NULL passed in), a catalog pertaining to all tables in the datasource accessible via this connection will be returned.
-
+The returned catalog will only contain catalog entries for tables to which the user specified in 'userID' has sufficient privileges. If no user is specified (NULL passed in), a catalog pertaining to all tables in the datasource accessible to the connected user (permissions apply) via this connection will be returned.
\membersection{wxDb::GetColumnCount}\label{wxdbgetcolumncount}
-\func{int}{GetColumnCount}{\param{char *}{tableName}, \param{const char *}{userID}}
+\func{int }{GetColumnCount}{\param{const wxString \&}{tableName}, \param{const wxChar *}{userID}}
\wxheading{Parameters}
-\docparam{tableName}{A table name you wish to obtain column information about.}
-\docparam{userID}{Name of the user that owns the table(s). Required for some datasources for
-situations where there may be multiple tables with the same name in the datasource, but owned
-by different users. {\it userID} is evaluated in the following manner:}
+\docparam{tableName}{The table name you wish to obtain column information about.}
+
+\docparam{userID}{Name of the user that owns the table(s) (also referred to as schema).
+Required for some datasources for situations where there may be multiple tables with the
+same name in the datasource, but owned by different users. {\it userID } is
+evaluated in the following manner:}
\begin{verbatim}
userID == NULL ... UserID is ignored (DEFAULT)
\wxheading{Return value}
-Returns a count of how many columns are in the specified table. If an error occurs retrieving the number of columns the function will return a -1.
-
+Returns a count of how many columns are in the specified table. If an error
+occurs retrieving the number of columns, this function will return a -1.
\membersection{wxDb::GetColumns}\label{wxdbgetcolumns}
-\func{wxDbColInf *}{GetColumns}{\param{char *}{tableName}, \param{int *}{numCols}, \param{const char *}{userID=NULL}}
+\func{wxDbColInf *}{GetColumns}{\param{const wxString \&}{tableName}, \param{UWORD *}{numCols}, \param{const wxChar *}{userID=NULL}}
-\func{wxDbColInf *}{GetColumns}{\param{char *}{tableName[]}, \param{const char *}{userID}}
+\func{wxDbColInf *}{GetColumns}{\param{wxChar *}{tableName[]}, \param{const wxChar *}{userID}}
\wxheading{Parameters}
-\docparam{tableName}{A table name you wish to obtain column information about.}
-\docparam{tableName[]}{An array of pointers to table names you wish to obtain column information about.
-The last element of this array must be a NULL string.}
-\docparam{numCols}{A pointer to a integer which will hold a count of the number
-of columns returned by this function}
-\docparam{userID}{Name of the user that owns the table(s). Required for some datasources for
-situations where there may be multiple tables with the same name in the datasource, but owned
-by different users. {\it userID} is evaluated in the following manner:}
+\docparam{tableName}{The table name you wish to obtain column information about.}
+\docparam{numCols}{Pointer to a UWORD which will hold a count of the number of columns returned by this function}
+\docparam{tableName[]}{An array of pointers to table names you wish to obtain column information about. The last element of this array must be a NULL string.}
+\docparam{userID}{Name of the user that owns the table(s) (also referred to as schema). Required for some datasources for situations where there may be multiple tables with the same name in the datasource, but owned by different users. {\it userID} is evaluated in the following manner:}
\begin{verbatim}
userID == NULL ... UserID is ignored (DEFAULT)
\wxheading{Return value}
-This function returns an array of wxDbColInf structures. This allows you to obtain
-information regarding the columns of your table(s). If no columns were found, or
-an error occured, this pointer will be zero (null).
+This function returns a pointer to an array of \helpref{wxDbColInf}{wxdbcolinf}
+structures, allowing you to obtain information regarding the columns of the
+named table(s). If no columns were found, or an error occurred, this pointer
+will be NULL.
THE CALLING FUNCTION IS RESPONSIBLE FOR DELETING THE {\it wxDbColInf} MEMORY WHEN IT IS
FINISHED WITH IT.
\normalbox{ALL column bindings associated with this wxDb instance are unbound
-by this function. This function should use its own wxDb instance
+by this function, including those used by any wxDbTable instances that use
+this wxDb instance. This function should use its own wxDb instance
to avoid undesired unbinding of columns.}
\wxheading{See also}
\helpref{wxDbColInf}{wxdbcolinf}
\wxheading{Example}
+
\begin{verbatim}
- char *tableList[] = {"PARTS", 0};
+ wxChar *tableList[] = {"PARTS", 0};
wxDbColInf *colInf = pDb->GetColumns(tableList);
if (colInf)
{
}
\end{verbatim}
-
\membersection{wxDb::GetData}\label{wxdbgetdata}
-\func{bool}{GetData}{\param{UWORD}{ colNo}, \param{SWORD}{ cType}, \param{PTR}{ pData}, \param{SDWORD}{ maxLen}, \param{SDWORD FAR *}{ cbReturned} }
+\func{bool}{GetData}{\param{UWORD}{ colNumber}, \param{SWORD}{ cType},
+\param{PTR}{ pData}, \param{SDWORD}{ maxLen}, \param{SDWORD FAR *}{ cbReturned} }
-Used to retrieve result set data without binding column values to memory variables (i.e. not using a wxDbTable instance to access table data).
+Used to retrieve result set data without binding column values to memory
+variables (i.e. not using a wxDbTable instance to access table data).
\wxheading{Parameters}
-\docparam{colNo}{Ordinal number of column in the result set to be returned.}
-\docparam{cType}{The C data type that is to be returned.}
-\docparam{pData}{Memory buffer which will hold the data returned by the call to this function.}
-\docparam{maxLen}{Maximum size of the buffer that will hold the returned value.}
-\docparam{cbReturned}{Pointer to the buffer containing the length of the actual data returned. If this value comes back as SQL_NULL_DATA, then the GetData() call has failed.}
+\docparam{colNumber}{Ordinal number of the desired column in the result set to be
+returned.}
+\docparam{cType}{The C data type that is to be returned. See a partial list
+in \helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs}}
+\docparam{pData}{Memory buffer which will hold the data returned by the call
+to this function.}
+\docparam{maxLen}{Maximum size of the buffer {\it 'pData'} in characters.
+NOTE: Not UNICODE safe. If this is a numeric field, a value of 0 may be
+passed for this parameter, as the API knows the size of the expected return
+value.}
+\docparam{cbReturned}{Pointer to the buffer containing the length of the
+actual data returned. If this value comes back as SQL\_NULL\_DATA, then the
+\helpref{wxDb::GetData}{wxdbgetdata} call has failed.}
\wxheading{See also}
\helpref{wxDb::GetNext}{wxdbgetnext}, \helpref{wxDb::ExecSql}{wxdbexecsql}
-\wxheading{Example}
+\wxheading{Example}
+
\begin{verbatim}
- SDWORD cb;
- ULONG reqQty;
- wxString sqlStmt;
- sqlStmt = "SELECT SUM(REQUIRED_QTY - PICKED_QTY) FROM ORDER_TABLE WHERE PART_RECID = 1450 AND REQUIRED_QTY > PICKED_QTY";
-
- // Perform the query
- if (!pDb->ExecSql(sqlStmt.c_str()))
- {
- // ERROR
- return(0);
- }
-
- // Request the first row of the result set
- if (!pDb->GetNext())
- {
- // ERROR
- return(0);
- }
-
- Read column #1 of this row of the result set and store the value in 'reqQty'
- if (!pDb->GetData(1, SQL_C_ULONG, &reqQty, 0, &cb))
- {
- // ERROR
- return(0);
- }
-
- // Check for a NULL result
- if (cb == SQL_NULL_DATA)
- return(0);
+ SDWORD cb;
+ ULONG reqQty;
+ wxString sqlStmt;
+ sqlStmt = "SELECT SUM(REQUIRED_QTY - PICKED_QTY) FROM ORDER_TABLE WHERE \
+ PART_RECID = 1450 AND REQUIRED_QTY > PICKED_QTY";
+
+ // Perform the query
+ if (!pDb->ExecSql(sqlStmt.c_str()))
+ {
+ // ERROR
+ return(0);
+ }
+
+ // Request the first row of the result set
+ if (!pDb->GetNext())
+ {
+ // ERROR
+ return(0);
+ }
+
+ // Read column #1 of the row returned by the call to ::GetNext()
+ // and return the value in 'reqQty'
+ if (!pDb->GetData(1, SQL_C_ULONG, &reqQty, 0, &cb))
+ {
+ // ERROR
+ return(0);
+ }
+
+ // Check for a NULL result
+ if (cb == SQL_NULL_DATA)
+ return(0);
\end{verbatim}
\wxheading{Remarks}
When requesting multiple columns to be returned from the result set (for example, the SQL query
-requested 3 columns be returned), the calls to GetData must request the columns in ordinal
-sequence (1,2,3 or 1,3 or 2,3).
-
+requested 3 columns be returned), the calls to this function must request the columns in ordinal
+sequence (1,2,3 or 1,3 or 2,3).
\membersection{wxDb::GetDatabaseName}\label{wxdbgetdatabasename}
-\func{char *}{GetDatabaseName}{\void}
+\func{const wxChar *}{GetDatabaseName}{\void}
Returns the name of the database engine.
+\membersection{wxDb::GetDatasourceName}\label{wxdbgetdatasourcename}
-\membersection{wxDb::GetDataSource}\label{wxdbgetdatasource}
-
-\func{char *}{GetDataSource}{\void}
+\func{const wxString \&}{GetDatasourceName}{\void}
Returns the ODBC datasource name.
-
\membersection{wxDb::GetHDBC}\label{wxdbgethdbc}
\func{HDBC}{GetHDBC}{\void}
Returns the ODBC handle to the database connection.
-
\membersection{wxDb::GetHENV}\label{wxdbgethenv}
\func{HENV}{GetHENV}{\void}
Returns the ODBC environment handle.
-
\membersection{wxDb::GetHSTMT}\label{wxdbgethstmt}
\func{HSTMT}{GetHSTMT}{\void}
Returns the ODBC statement handle associated with this database connection.
-
\membersection{wxDb::GetKeyFields}\label{wxdbgetkeyfields}
-\func{int}{GetKeyFields}{\param{char *}{tableName}, \param{wxDbColInf *}{colInf}, \param{int}{nocols}}
+\func{int }{GetKeyFields}{\param{const wxString \&}{tableName}, \param{wxDbColInf *}{colInf}, \param{UWORD }{numColumns}}
Used to determine which columns are members of primary or non-primary indexes on the specified table. If a column is a member of a foreign key for some other table, that information is detected also.
-This function is primarily for use by the wxDb::GetColumns() function, but may be called if desired from the client application.
+This function is primarily for use by the \helpref{wxDb::GetColumns}{wxdbgetcolumns} function, but may be called if desired from the client application.
\wxheading{Parameters}
\docparam{tableName}{Name of the table for which the columns will be evaluated as to their inclusion in any indexes.}
-\docparam{colInf}{Data structure containing the column definitions (obtained with wxDb::GetColumns()). This function populates the PkCol, PkTableName, and FkTableName members of the colInf structure.}
-\docparam{nocols}{Number of columns defined in the instance of colInf.}
+\docparam{colInf}{Data structure containing the column definitions (obtained with \helpref{wxDb::GetColumns}{wxdbgetcolumns}). This function populates the PkCol, PkTableName, and FkTableName members of the colInf structure.}
+\docparam{numColumns}{Number of columns defined in the instance of colInf.}
\wxheading{Return value}
-Currently always returns TRUE.
+Currently always returns true.
\wxheading{See also}
\helpref{wxDbColInf}{wxdbcolinf}, \helpref{wxDb::GetColumns}{wxdbgetcolumns}
-
\membersection{wxDb::GetNext}\label{wxdbgetnext}
-\func{HSTMT}{GetNext}{\void}
+\func{bool}{GetNext}{\void}
-Requests the next row in the result set obtained by issueing a query through a direct request using wxDb::ExecSql().
+Called after executing a query, this function requests the next row
+in the result set after the current position of the cursor.
\wxheading{See also}
\helpref{wxDb::ExecSql}{wxdbexecsql}, \helpref{wxDb::GetData}{wxdbgetdata}
-
\membersection{wxDb::GetNextError}\label{wxdbgetnexterror}
-\func{bool}{GetNextError}{\param{HENV}{ aHenv}, \param{HDBC}{ aHdbc = SQL_NULL_HDBC}, \param{HSTMT}{ aHstmt = SQL_NULL_HSTMT}}
+\func{bool}{GetNextError}{\param{HENV}{ aHenv},
+\param{HDBC}{ aHdbc = SQL\_NULL\_HDBC}, \param{HSTMT}{ aHstmt = SQL\_NULL\_HSTMT}}
\wxheading{Parameters}
\docparam{aHenv}{A handle to the ODBC environment.}
-\docparam{aHdbc}{A handle to the ODBC connection. Pass this in if the ODBC function call that
-erred out required a hdbc or hstmt argument.}
-\docparam{AHstmt}{A handle to the ODBC statement being executed against. Pass this in if the
-ODBC function call that erred out requires a hstmt argument.}
-
-\wxheading{See also}
+\docparam{aHdbc}{{\it OPTIONAL.} A handle to the ODBC connection. Pass this
+in if the ODBC function call that failed required a hdbc or hstmt argument.}
+\docparam{AHstmt}{{\it OPTIONAL.}A handle to the ODBC statement being executed
+against. Pass this in if the ODBC function call that failed requires a
+hstmt argument.}
-\helpref{wxDb::DispNextError}{wxdbdispnexterror}, \helpref{wxDb::DispAllErrors}{wxdbdispallerrors}
+\wxheading{Example}
-\wxheading{Example}
\begin{verbatim}
if (SQLExecDirect(hstmt, (UCHAR FAR *) pSqlStmt, SQL_NTS) != SQL_SUCCESS)
{
- // Display all ODBC errors for this stmt
- return(db.DispAllErrors(db.henv, db.hdbc, hstmt));
+ return(db.GetNextError(db.henv, db.hdbc, hstmt));
}
\end{verbatim}
+\wxheading{See also}
+
+\helpref{wxDb::DispNextError}{wxdbdispnexterror},
+\helpref{wxDb::DispAllErrors}{wxdbdispallerrors}
+
\membersection{wxDb::GetPassword}\label{wxdbgetpassword}
-\func{char *}{GetPassword}{\void}
+\func{const wxString \&}{GetPassword}{\void}
-Returns the password used to connect to the datasource.
+Returns the password used to establish this connection to the datasource.
\membersection{wxDb::GetTableCount}\label{wxdbgettablecount}
-\func{int}{GetTableCount}{\void}
+\func{int }{GetTableCount}{\void}
-Returns the number of wxDbTable() instances currently using this data source connection.
+Returns the number of wxDbTable() instances currently using this datasource
+connection.
\membersection{wxDb::GetUsername}\label{wxdbgetusername}
-\func{char *}{GetUsername}{\void}
+\func{const wxString \&}{GetUsername}{\void}
-Returns the user name used to access the datasource.
+Returns the user name (uid) used to establish this connection to the
+datasource.
\membersection{wxDb::Grant}\label{wxdbgrant}
-\func{bool}{Grant}{\param{int}{ privileges}, \param{char *}{tableName}, \param{char *}{userList = "PUBLIC"}}
+\func{bool}{Grant}{\param{int }{privileges}, \param{const wxString \&}{tableName},
+\param{const wxString \&}{userList = "PUBLIC"}}
-Use this member function to GRANT privileges to users for accessing tables in the datasource.
+Use this member function to GRANT privileges to users for accessing tables in
+the datasource.
\wxheading{Parameters}
-\docparam{privileges}{Use this argument to select which privileges you want to grant. Pass
- DB_GRANT_ALL to grant all privileges. To grant individual privileges pass
- one or more of the following OR'd together:}
+\docparam{privileges}{Use this argument to select which privileges you want to
+grant. Pass DB\_GRANT\_ALL to grant all privileges. To grant individual
+privileges pass one or more of the following OR'd together:}
+
\begin{verbatim}
DB_GRANT_SELECT = 1
DB_GRANT_INSERT = 2
DB_GRANT_ALL = DB_GRANT_SELECT | DB_GRANT_INSERT |
DB_GRANT_UPDATE | DB_GRANT_DELETE
\end{verbatim}
+
\docparam{tableName}{The name of the table you wish to grant privileges on.}
-\docparam{userList}{A comma delimited list of users to grant the privileges to. If this argument is not
-passed in, the privileges will be given to the general PUBLIC.}
+\docparam{userList}{{\it OPTIONAL.} A comma delimited list of users to grant the privileges to. If this argument is not passed in, the privileges will be given to the general PUBLIC.}
\wxheading{Remarks}
Some databases require user names to be specified in all capital letters (i.e. Oracle). This function does not automatically capitalize the user names passed in the comma-separated list. This is the responsibility of the calling routine.
-\wxheading{Example}
+The currently logged in user must have sufficient grantor privileges for this
+function to be able to successfully grant the indicated privileges.
+
+\wxheading{Example}
+
\begin{verbatim}
db.Grant(DB_GRANT_SELECT | DB_GRANT_INSERT, "PARTS", "mary, sue");
\end{verbatim}
+\membersection{wxDb::IsFwdOnlyCursors}\label{wxdbisfwdonlycursors}
+
+\func{bool}{IsFwdOnlyCursors}{\void}
+
+This setting indicates whether this database connection was created
+as being capable of using only forward scrolling cursors.
+
+This function does NOT indicate if the ODBC driver or datasource supports
+backward scrolling cursors. There is no standard way of detecting if the
+driver or datasource can support backward scrolling cursors.
+
+If a wxDb instance was created as being capable of only forward scrolling
+cursors, then even if the datasource and ODBC driver support backward
+scrolling cursors, tables using this database connection would only be able
+to use forward scrolling cursors.
+
+The default setting of whether a wxDb connection to a database allows
+forward-only or also backward scrolling cursors is defined in setup.h by the
+value of wxODBC\_FWD\_ONLY\_CURSORS. This default setting can be overridden
+when the wxDb connection is initially created (see
+\helpref{wxDb constructor}{wxdbctor} and \helpref{wxDbGetConnection}{wxdbfunctions}).
+
+\wxheading{Return value}
+
+Returns true if this datasource connection is defined as using only forward
+scrolling cursors, or false if the connection is defined as being allowed to
+use backward scrolling cursors and their associated functions (see note above).
+
+\wxheading{Remarks}
+
+Added as of wxWidgets v2.4 release, this function is a renamed version of
+wxDb::FwdOnlyCursors() to match the normal wxWidgets naming conventions for
+class member functions.
+
+This function is not available in versions prior to v2.4. You should
+use \helpref{wxDb::FwdOnlyCursors}{wxdbfwdonlycursors} for wxWidgets
+versions prior to 2.4.
+
+\wxheading{See also}
+
+\helpref{wxDb constructor}{wxdbctor}, \helpref{wxDbGetConnection}{wxdbfunctions}
\membersection{wxDb::IsOpen}\label{wxdbisopen}
\func{bool}{IsOpen}{\void}
-Indicates whether the database connection to the datasource is currently opened.
+Indicates whether the database connection to the datasource is currently
+opened.
+
+\wxheading{Remarks}
+
+This function may indicate that the database connection is open, even if
+the call to \helpref{wxDb::Open}{wxdbopen} may have failed to fully
+initialize the connection correctly. The connection to the database
+{\it is} open and can be used via the direct SQL commands, if this
+function returns true. Other functions which depend on the
+\helpref{wxDb::Open}{wxdbopen} to have completed correctly may not function
+as expected. The return result from \helpref{wxDb::Open}{wxdbopen} is the
+only way to know if complete initialization of this wxDb connection was
+successful or not. See \helpref{wxDb::Open}{wxdbopen} for more details on
+partial failures to open a connection instance.
+
+\membersection{wxDb::LogError}\label{wxdblogerror}
+
+\func{void}{LogError}{\param{const wxString \&}{errMsg} \param{const wxString \&}{SQLState=""}}
+
+\docparam{errMsg}{Free-form text to display describing the error/text to be logged.}
+\docparam{SQLState}{{\it OPTIONAL.} Native SQL state error. Default is 0.}
+
+\wxheading{Remarks}
+
+Calling this function will enter a log message in the error list maintained
+for the database connection. This log message is free form and can be
+anything the programmer wants to enter in the error list.
+
+If SQL logging is turned on, the call to this function will also log the
+text into the SQL log file.
+
+\wxheading{See also}
+
+\helpref{wxDb::WriteSqlLog}{wxdbwritesqllog}
+
+\membersection{wxDb::ModifyColumn}\label{wxdbmodifycolumn}
+
+\func{void}{ModifyColumn}{\param{const wxString \&}{tableName} \param{const wxString \&}{ColumnName}
+\param{int }{dataType} \param{ULONG }{columnLength=0} \param{const wxString \&}{optionalParam=""}}
+
+Used to change certain properties of a column such as the length, or whether a column
+allows NULLs or not.
+
+\docparam{tableName}{Name of the table that the column to be modified is in.}
+\docparam{columnName}{Name of the column to be modified. NOTE: Name of column cannot
+be changed with this function.}
+\docparam{dataType}{Any one of DB\_DATA\_TYPE\_VARCHAR, DB\_DATA\_TYPE\_INTEGER,
+DB\_DATA\_TYPE\_FLOAT, DB\_DATA\_TYPE\_DATE.}
+\docparam{columnLength}{New size of the column. Valid only for DB\_DATA\_TYPE\_VARCHAR
+dataType fields. Default is 0.}
+\docparam{optionalParam}{Default is "".}
+
+\wxheading{Remarks}
+
+Cannot be used to modify the precision of a numeric column, therefore 'columnLength'
+is ignored unless the dataType is DB\_DATA\_TYPE\_VARCHAR.
+
+Some datasources do not allow certain properties of a column to be changed if any rows
+currently have data stored in that column. Those datasources that do allow columns
+to be changed with data in the rows many handle truncation and/or expansion in
+different ways. Please refer to the reference material for the datasource being
+used for behavioral descriptions.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ ok = pDb->ModifyColumn("CONTACTS", "ADDRESS2",
+ DB_, colDefs[j].SzDataObj,
+ wxT("NOT NULL"));
+\end{verbatim}
\membersection{wxDb::Open}\label{wxdbopen}
-\func{bool}{Open}{\param{char *}{Dsn}, \param{char *}{Uid}, \param{char *}{AuthStr}}
+\func{bool}{Open}{\param{const wxString \&}{Dsn}, \param{const wxString \&}{Uid},
+\param{const wxString \&}{AuthStr}, \param{bool }{failOnDataTypeUnsupported}}
+
+\func{bool}{Open}{\param{const wxString \&}{inConnectStr},
+\param{bool }{failOnDataTypeUnsupported}}
+
+\func{bool}{Open}{\param{wxDbConnectInf *}{dbConnectInf},
+\param{bool }{failOnDataTypeUnsupported}}
+
+\func{bool}{Open}{\param{wxDb *}{copyDb}}
+
+Opens a connection to the datasource, sets certain behaviors of the datasource
+to confirm to the accepted behaviors (e.g. cursor position maintained on
+commits), and queries the datasource for its representations of the basic
+datatypes to determine the form in which the data going to/from columns in
+the data tables are to be handled.
+
+The second form of this function, which accepts a "wxDb *" as a parameter,
+can be used to avoid the overhead (execution time, database load, network
+traffic) which are needed to determine the data types and representations
+of data that are necessary for cross-datasource support by these classes.
+
+Normally the first form of the wxDb::Open() function will open the connection
+and then send a series of queries to the datasource asking it for its
+representation of data types, and all the features it supports. If one
+connection to the datasource has already been made previously, the information
+gathered when that connection was created can just be copied to any new
+connections to the same datasource by passing a pointer to the first
+connection in as a parameter to the wxDb::Open() function. Note that this
+new connection created from the first connections information will use the
+same Dsn/Uid/AuthStr as the first connection used.
\wxheading{Parameters}
-\docparam{Dsn}{Data source name. The name of the ODBC data source as
-assigned when the data source is initially set up through the ODBC data
+\docparam{Dsn}{datasource name. The name of the ODBC datasource as
+assigned when the datasource is initially set up through the ODBC data
source manager.}
\docparam{Uid}{User ID. The name (ID) of the user you wish to connect as
-to the data source. The user name (ID) determines what objects you
+to the datasource. The user name (ID) determines what objects you
have access to in the datasource and what datasource privileges you have.
Privileges include being able to create new objects, update objects, delete
objects and so on. Users and privileges are normally administered by the
database administrator.}
-\docparam{AuthStr}{The password associated witht the Uid.}
+\docparam{AuthStr}{The password associated with the Uid.}
+\docparam{failOnDataTypeUnsupporte}{As part of connecting to a database, the
+wxDb::Open() function will query the database to find out the native types
+that it supports. With some databases, some data types may not be supported,
+or not sufficiently supported, for use with the wxODBC classes. Normally
+a program should fail in this case, so as not to try to use a data type
+that is not supported. This parameter allows the programmer to override the
+failure if they wish and continue on using the connection.}
+\docparam{dbConnectInf}{Contains a DSN, Uid, Password, or a connection string
+to be used in opening a new connection to the database. If a connection
+string is present, then the connection string will be used. If there is no
+connection string present, then the DSN, Uid, and Password are used.}
+\docparam{inConnectStr}{A valid ODBC connection string used to connect to a
+database}
+\docparam{copyDb}{Already completely configured and opened datasource
+connection from which all Dsn, Uid, AuthStr, connection string, and data
+typing information is to be copied from for use by this datasource
+connection. If 'copyDb' used a connection string to create its connection
+originally, then the connection being made by this call to wxDb::Open() will
+use that same connection string.}
\wxheading{Remarks}
-After a wxDb instance is created, it must then be opened. When opening a data source, there must be hree pieces of information passed. The data source name, user name (ID) and the password for the user. No database activity on the data source can be performed until it is opened. This would normally be done at program startup and the data source would remain open for the duration of the program run. Note: It is possible to have multiple data sources open at the same time to support distributed database connections.
+After a wxDb instance is created, it must then be opened. When opening a
+datasource, there must be three pieces of information passed. The data
+source name, user name (ID) and the password for the user. No database
+activity on the datasource can be performed until the connection is opened.
+This is normally done at program startup and the datasource remains
+open for the duration of the program/module run.
+
+It is possible to have connections to multiple datasources open at the same
+time to support distributed database connections by having separate instances
+of wxDb objects that use either the same or different Dsn/Uid/AuthStr settings.
+
+If this function returns a value of false, it does not necessarily mean that
+the connection to the datasource was not opened. It may mean that some
+portion of the initialization of the connection failed (such as a datatype not
+being able to be determined how the datasource represents it). To determine
+if the connection to the database failed, use the \helpref{wxDb::IsOpen}{wxdbisopen}
+function after receiving a false result back from this function to determine if
+the connection was opened or not. If this function returns false, but \helpref{wxDb::IsOpen}{wxdbisopen}
+returns true, then direct SQL commands may be passed to the database
+connection and can be successfully executed, but use of the datatypes (such as
+by a wxDbTable instance) that are normally determined during open will not be
+possible.
+
+\normalbox{The {\it Dsn}, {\it Uid}, and {\it AuthStr} string pointers that are passed in
+are copied. NOT the strings themselves, only the pointers. The calling routine
+must maintain the memory for these three strings for the life of the wxDb instance.}
\wxheading{Example}
+
\begin{verbatim}
- wxDb sampleDB(Db.Henv);
+ wxDb sampleDB(DbConnectInf.GetHenv());
if (!sampleDB.Open("Oracle 7.1 HP/UX", "gtasker", "myPassword"))
{
- // Error opening data source
+ if (sampleDb.IsOpen())
+ {
+ // Connection is open, but the initialization of
+ // datatypes and parameter settings failed
+ }
+ else
+ {
+ // Error opening datasource
+ }
}
\end{verbatim}
-
\membersection{wxDb::RollbackTrans}\label{wxdbrollbacktrans}
\func{bool}{RollbackTrans}{\void}
-Function to "rollback" changes made to the database. After an insert/update/delete, the operation may be "undone" by issuing this command any time before a \helpref{wxDb::CommitTrans}{wxdbcommittrans} is called on the database connection.
+Function to "undo" changes made to the database. After an insert/update/delete, the operation may be "undone" by issuing this command any time before a \helpref{wxDb::CommitTrans}{wxdbcommittrans} is called on the database connection.
\wxheading{Remarks}
-Transactions begin implicitly as soon as you make a change to the database. At any time thereafter, you can save your work to the database (using \helpref{wxDb::CommitTrans}{wxdbcommittrans}) or undo all of your changes using this function.
+Transactions begin implicitly as soon as you make a change to the database. The
+transaction continues until either a commit or rollback is executed. Calling
+wxDb::RollbackTrans() will result in ALL changes done using this database
+connection that have not already been committed to be "undone" back to the last
+commit/rollback that was successfully executed.
-\normalbox{Calling this member function rolls back ALL open (uncommitted) transactions on this ODBC connection.}
+\normalbox{Calling this member function rolls back ALL open (uncommitted)
+transactions on this ODBC connection, including all wxDbTable instances that
+use this connection.}
\wxheading{See also}
\helpref{wxDb::CommitTrans}{wxdbcommittrans} for a special note on cursors
+\membersection{wxDb::SetDebugErrorMessages}\label{wxdbsetdebugerrormessages}
-\membersection{wxDb::SetSqlLogging}\label{wxdbsetsqllogging}
-
-\func{bool}{SetSqlLogging}{\param{wxDbSqlLogState}{ state}, \param{const wxChar *}{filename = SQL_LOG_FILENAME}, \param{bool}{ append = FALSE}}
-
-\wxheading{Parameters}
+\func{void}{SetDebugErrorMessages}{\param{bool }{state}}
-\docparam{state}{Either sqlLogOFF or sqlLogON (see \helpref{enum wxDbSqlLogState}{wxdbenumsqllogstate}). Turns logging of SQL commands sent to the data
-source OFF or ON.}
-\docparam{filename}{{\it OPTIONAL}. Name of the file to which the log text is to be written.}
-\docparam{append}{{\it OPTIONAL}. Whether the file is appended to or overwritten.}
+\docparam{state}{Either true (debug messages are logged) or false (debug
+messages are not logged).}
\wxheading{Remarks}
-When called with {\it sqlLogON}, all commands sent to the data source engine are logged to the file specified by {\it filename}. Logging is done by embedded WriteSqlLog() calls in the database member functions, or may be manually logged by adding calls to WriteSqlLog() in your own source code.
+Turns on/off debug error messages from the ODBC class library. When
+this function is passed true, errors are reported to the user/logged automatically
+in a text or pop-up dialog when an ODBC error occurs. When passed false,
+errors are silently handled.
-When called with {\it sqlLogOFF}, the logging file is closed, and any calls to WriteSqlLog() are ignored.
+When compiled in release mode (FINAL=1), this setting has no affect.
+\wxheading{See also}
-\membersection{wxDb::TableExists}\label{wxdbtablexists}
+\helpref{wxDb constructor}{wxdbctor}
-\func{bool}{TableExists}{\param{const char *}{tableName}, \param{const char *}{userID=NULL}, \param{const char *}{path=NULL}}
+\membersection{wxDb::SetSqlLogging}\label{wxdbsetsqllogging}
-Checks the ODBC data source for the existence of a table. If a {\it userID} is specified, then the table must be accessible by that user (user must have at least minimal privileges to the table).
+\func{bool}{SetSqlLogging}{\param{wxDbSqlLogState}{ state}, \param{const wxString \&}{filename = SQL\_LOG\_FILENAME}, \param{bool }{ append = false}}
\wxheading{Parameters}
-\docparam{tableName}{Name of the table to check for the existence of}
-\docparam{userID}{Owner of the table. Specify a userID when the datasource you are connected
-to allows multiple unique tables with the same name to be owned by different users. {\it userID}
-is evaluated as follows:}
-
-\begin{verbatim}
- userID == NULL ... UserID is ignored (DEFAULT)
- userID == "" ... UserID set equal to 'this->uid'
- userID != "" ... UserID set equal to 'userID'
-\end{verbatim}
+\docparam{state}{Either sqlLogOFF or sqlLogON (see \helpref{enum wxDbSqlLogState}{wxdbcolfor}). Turns logging of SQL commands sent to the datasource OFF or ON.}
+\docparam{filename}{{\it OPTIONAL}. Name of the file to which the log text is to be written. Default is SQL\_LOG\_FILENAME.}
+\docparam{append}{{\it OPTIONAL}. Whether the file is appended to or overwritten. Default is false.}
\wxheading{Remarks}
-{\it tableName} may refer to a table, view, alias or synonym.
+When called with {\it sqlLogON}, all commands sent to the datasource engine are logged to the file specified by {\it filename}. Logging is done by embedded \helpref{wxDb::WriteSqlLog}{wxdbwritesqllog} calls in the database member functions, or may be manually logged by adding calls to \helpref{wxDb::WriteSqlLog}{wxdbwritesqllog} in your own source code.
-This function does not indicate whether or not the user has privleges to query or perform other functions on the table.
+When called with {\it sqlLogOFF}, the logging file is closed, and any calls to \helpref{wxDb::WriteSqlLog}{wxdbwritesqllog} are ignored.
+\membersection{wxDb::SQLColumnName}\label{wxdbsqlcolumnname}
-\membersection{wxDb::TranslateSqlState}\label{wxdbtranslatesqlstate}
+\func{const wxString}{SQLColumnName}{\param{const char *}{ colName}}
-\func{int}{TranslateSqlState}{\param{const wxChar *}{SQLState}}
+Returns the column name in a form ready for use in SQL statements.
+In most cases, the column name is returned verbatim. But some databases
+(e.g. MS Access, SQL Server, MSDE) allow for spaces in column names, which
+must be specially quoted. For example, if the datasource allows spaces
+in the column name, the returned string will have the correct enclosing
+marks around the name to allow it to be properly included in a SQL statement
+for the DBMS that is currently connected to with this connection.
\wxheading{Parameters}
-\docparam{SQLState}{Converts an ODBC sqlstate to an internal error code.}
+\docparam{colName}{Native name of the column in the table that is to be
+evaluated to determine if any special quoting marks needed to be added to it
+before including the column name in a SQL statement}
-\wxheading{Return value}
+\wxheading{See also}
-Returns the internal class DB_ERR code. See \helpref{wxDb::DB_STATUS}{wxdbdbstatus} definition.
+\helpref{wxDb::SQLTableName}{wxdbsqltablename}
+\membersection{wxDb::SQLTableName}\label{wxdbsqltablename}
-\membersection{wxDb::WriteSqlLog}\label{wxdbwritesqllog}
+\func{const wxString}{SQLTableName}{\param{const char *}{ tableName}}
-\func{bool}{WriteSqlLog}{\param{const wxChar *}{logMsg}}
+Returns the table name in a form ready for use in SQL statements.
+In most cases, the table name is returned verbatim. But some databases
+(e.g. MS Access, SQL Server, MSDE) allow for spaces in table names, which
+must be specially quoted. For example, if the datasource allows spaces
+in the table name, the returned string will have the correct enclosing
+marks around the name to allow it to be properly included in a SQL statement
+for the data source that is currently connected to with this connection.
\wxheading{Parameters}
-\docparam{logMsg}{Free form string to be written to the log file.}
+\docparam{tableName}{Native name of the table that is to be evaluated to
+determine if any special quoting marks needed to be added to it
+before including the table name in a SQL statement}
-\wxheading{Remarks}
+\wxheading{See also}
-Very useful debugging tool that may be turned on/off during run time. The
-passed in string {\it logMsg} will be written to a log file if SQL logging
-is turned on (see \helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging} for details on turning logging on/off).
+\helpref{wxDb::SQLColumnName}{wxdbsqlcolumnname}
-\wxheading{Return value}
+\membersection{wxDb::TableExists}\label{wxdbtableexists}
-If SQL logging is off when a call to WriteSqlLog() is made, or there is a
-failure to write the log message to the log file, the function returns
-FALSE without performing the requested log, otherwise TRUE is returned.
+\func{bool}{TableExists}{\param{const wxString \&}{tableName}, \param{const wxChar *}{userID=NULL}, \param{const wxString \&}{path=""}}
-\wxheading{See also}
+Checks the ODBC datasource for the existence of a table. If a {\it userID}
+is specified, then the table must be accessible by that user (user must have
+at least minimal privileges to the table).
-\helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging}
+\wxheading{Parameters}
-==============
-\membersection{wxDb::IsFwdOnlyCursors}\label{wxdbisfwdonlycursors}
+\docparam{tableName}{Name of the table to check for the existence of.}
+\docparam{userID}{Owner of the table (also referred to as schema). Specify a userID when the datasource you are connected
+to allows multiple unique tables with the same name to be owned by different users. {\it userID}
+is evaluated as follows:}
-\func{bool}{IsFwdOnlyCursors}{\void}
+\begin{verbatim}
+ userID == NULL ... UserID is ignored (DEFAULT)
+ userID == "" ... UserID set equal to 'this->uid'
+ userID != "" ... UserID set equal to 'userID'
+\end{verbatim}
\wxheading{Remarks}
-This setting indicates whether this database connection was created
-as being capable of using only forward scrolling cursors. This function
-does NOT indicate if the ODBC driver or datasource supports backward
-scrolling cursors. There is no standard way of detecting if the driver
-or datasource can support backward scrolling cursors.
+{\it tableName} may refer to a table, view, alias or synonym.
-If a wxDb instance was created as being forward only cursors, then even if
-the datasource and ODBC driver support backward scrolling cursors, then
-tables using this database connection can only use forward scrolling
-cursors.
+This function does not indicate whether or not the user has privileges to query or perform other functions on the table. Use the \helpref{wxDb::TablePrivileges}{wxdbtableprivileges} to determine if the user has sufficient privileges or not.
-The default setting of whether a wxDb connection to a database allows
-forward-only or also backward scrolling cursors is defined in setup.h by
-the wxODBC_FWD_ONLY_CURSORS value. This default setting can be overridden
-when the wxDb connection is initially created (see \helpref{wxDb constructor}{wxdbconstr}).
+\wxheading{See also}
-\wxheading{Return value}
+\helpref{wxDb::TablePrivileges}{wxdbtableprivileges}
-Returns TRUE if this datasource connection is defined as using only forward
-scrolling cursors, or FALSE if the connection is defined as being capable
-of supporting backward scrolling cursors (see note above).
+\membersection{wxDb::TablePrivileges}\label{wxdbtableprivileges}
-\wxheading{See also}
+\func{bool}{TablePrivileges}{\param{const wxString \&}{tableName}, \param{const wxString \&}{priv},
+\param{const wxChar *}{userID=NULL}, \param{const wxChar *}{schema=NULL},
+\param{const wxString \&}{path=""}}
-\helpref{wxDb constructor}{wxdbconstr}
+Checks the ODBC datasource for the existence of a table. If a {\it userID}
+is specified, then the table must be accessible by that user (user must have
+at least minimal privileges to the table).
-=======
-\membersection{wxDb::Dbms}\label{wxdbdbms}
+\wxheading{Parameters}
+
+\docparam{tableName}{Name of the table on which to check privileges.
+{\it tableName} may refer to a table, view, alias or synonym.}
+\docparam{priv}{The table privilege being evaluated. May be one of the
+following (or a datasource specific privilege):}
+
+\begin{verbatim}
+ SELECT : The connected user is permitted to retrieve data for
+ one or more columns of the table.
+
+ INSERT : The connected user is permitted to insert new rows
+ containing data for one or more columns into the
+ table.
+
+ UPDATE : The connected user is permitted to update the data in
+ one or more columns of the table.
+
+ DELETE : The connected user is permitted to delete rows of
+ data from the table.
+
+ REFERENCES : Is the connected user permitted to refer to one or
+ more columns of the table within a constraint (for
+ example, a unique, referential, or table check
+ constraint).
+\end{verbatim}
+
+\docparam{userID}{{\it OPTIONAL.} User for which to determine if the privilege
+specified to be checked is granted or not. Default is "".
+{\it userID} is evaluated as follows:}
+
+\begin{verbatim}
+ userID == NULL ... NOT ALLOWED!
+ userID == "" ... UserID set equal to 'this->uid'
+ userID != "" ... UserID set equal to 'userID'
+\end{verbatim}
+
+\docparam{schema}{{\it OPTIONAL.} Owner of the table. Specify a userID when the datasource
+you are connected to allows multiple unique tables with the same name to be
+owned by different users. Specifying the table owner makes determination of the
+users privileges MUCH faster. Default is NULL. {\it userID} is
+evaluated as follows:}
+
+\begin{verbatim}
+ schema == NULL ... Any owner (DEFAULT)
+ schema == "" ... Owned by 'this->uid'
+ schema != "" ... Owned by userID specified in 'schema'
+\end{verbatim}
+
+\docparam{path}{{\it OPTIONAL.} Path to the table. Default is "".
+Currently unused.}
+
+\wxheading{Remarks}
+
+The scope of privilege allowed to the connected user by a given table
+privilege is datasource dependent.
+
+For example, the privilege UPDATE might allow the connected user to update
+all columns in a table on one datasource, but only those columns for
+which the grantor (the user that granted the connected user) has the UPDATE
+privilege on another datasource.
+
+Looking up a user's privileges to a table can be time consuming depending on the
+datasource and ODBC driver. This time can be minimized by passing a {\it schema}
+as a parameter. With some datasources/drivers, the difference can be several
+seconds of time difference.
+
+
+\membersection{wxDb::TranslateSqlState}\label{wxdbtranslatesqlstate}
+
+\func{int }{TranslateSqlState}{\param{const wxString \&}{SQLState}}
+
+Converts an ODBC sqlstate to an internal error code.
+
+\wxheading{Parameters}
+
+\docparam{SQLState}{State to be converted.}
+
+\wxheading{Return value}
+
+Returns the internal class DB\_ERR code. See \helpref{wxDb::DB\_STATUS}{wxdb} definition.
+
+\membersection{wxDb::WriteSqlLog}\label{wxdbwritesqllog}
+
+\func{bool}{WriteSqlLog}{\param{const wxString \&}{logMsg}}
+
+\wxheading{Parameters}
+
+\docparam{logMsg}{Free form string to be written to the log file.}
+
+\wxheading{Remarks}
+
+Very useful debugging tool that may be turned on/off during run time (see
+(see \helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging} for details on
+turning logging on/off). The passed in string {\it logMsg} will be written to
+a log file if SQL logging is turned on.
+
+\wxheading{Return value}
+
+If SQL logging is off when a call to WriteSqlLog() is made, or there is a
+failure to write the log message to the log file, the function returns
+false without performing the requested log, otherwise true is returned.
+
+\wxheading{See also}
+
+\helpref{wxDb::SetSqlLogging}{wxdbsetsqllogging}
+
+\section{\class{wxDbColDataPtr}}\label{wxdbcoldataptr}
+
+Pointer to dynamic column definitions for use with a wxDbTable instance.
+Currently there are no member functions for this class.
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+\begin{verbatim}
+ void *PtrDataObj;
+ int SzDataObj;
+ SWORD SqlCtype;
+\end{verbatim}
+
+\section{\class{wxDbColDef}}\label{wxdbcoldef}
+
+This class is used to hold information about the columns bound to an
+instance of a wxDbTable object.
+
+Each instance of this class describes one column in the wxDbTable
+object. When calling the \helpref{wxDb constructor}{wxdbctor}, a
+parameter passed in indicates the number of columns that will be defined for
+the wxDbTable object. The constructor uses this information to allocate
+adequate memory for all of the column descriptions in your wxDbTable object.
+Private member wxDbTable::colDefs is a pointer to this chunk of memory
+maintained by the wxDbTable class (and can be retrieved using the
+\helpref{wxDbTable::GetColDefs}{wxdbtablegetcoldefs} function).
+To access the nth column definition of your wxDbTable object, just reference
+wxDbColDefs element [n - 1].
+
+Typically, \helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs} is used to
+populate an array of these data structures for the wxDbTable instance.
+
+Currently there are no accessor functions for this class, so all members are
+public.
+
+\begin{verbatim}
+ wxChar ColName[DB_MAX_COLUMN_NAME_LEN+1]; // Column Name
+ int DbDataType; - Logical Data Type;
+ e.g. DB_DATA_TYPE_INTEGER
+ SWORD SqlCtype; - C data type; e.g. SQL_C_LONG
+ void *PtrDataObj; - Address of the data object
+ int SzDataObj; - Size, in bytes, of the data object
+ bool KeyField; - Is column part of the PRIMARY KEY for the
+ table? -- Date fields should NOT be
+ KeyFields
+ bool Updateable; - Column is updateable?
+ bool InsertAllowed; - Column included in INSERT statements?
+ bool DerivedCol; - Column is a derived value?
+ SDWORD CbValue; - !!!Internal use only!!!
+ bool Null; - NOT FULLY IMPLEMENTED
+ Allows NULL values in Inserts and Updates
+\end{verbatim}
+
+\wxheading{See also}
+
+\helpref{database classes overview}{odbcoverview},
+\helpref{wxDbTable::GetColDefs}{wxdbtablegetcoldefs}, \helpref{wxDb constructor}{wxdbctor}
+
+\wxheading{Include files}
+
+<wx/db.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDbColDef::Initialize}\label{wxdbcoldefinitialize}
+
+Simply initializes all member variables to a cleared state. Called by
+the constructor automatically.
+
+\section{\class{wxDbColFor}}\label{wxdbcolfor}
+
+Beginning support for handling international formatting specifically on dates
+and floats.
+
+\begin{verbatim}
+ wxString s_Field; // Formatted String for Output
+ wxString s_Format[7]; // Formatted Objects - TIMESTAMP has
+ the biggest (7)
+ wxString s_Amount[7]; // Formatted Objects - amount of
+ things that can be formatted
+ int i_Amount[7]; // Formatted Objects -
+ TT MM YYYY HH MM SS m
+ int i_Nation; // 0 = timestamp
+ 1 = EU
+ 2 = UK
+ 3 = International
+ 4 = US
+ int i_dbDataType; // conversion of the 'sqlDataType'
+ to the generic data type used by
+ these classes
+ SWORD i_sqlDataType;
+\end{verbatim}
+
+The constructor for this class initializes all the values to zero or NULL.
+
+The destructor does nothing at this time.
+
+Only one function is provided with this class currently.
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+\wxheading{Include files}
+
+<wx/db.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDbColFor::Format}\label{wxdbcolforformat}
+
+\func{int }{Format}{\param{int }{Nation}, \param{int }{dbDataType},
+\param{SWORD }{sqlDataType}, \param{short }{columnSize},
+\param{short }{decimalDigits}}\label{wxdbcolforformat}
+
+Work in progress, and should be inter-related with wxLocale eventually.
+
+\membersection{wxDbColFor::Initialize}\label{wxdbcolforinitialize}
+
+Simply initializes all member variables to a cleared state. Called by
+the constructor automatically.
+
+\section{\class{wxDbColInf}}\label{wxdbcolinf}
+
+Used with the \helpref{wxDb::GetColumns}{wxdbgetcolumns} functions for obtaining all retrievable information about a column's definition.
+
+\begin{verbatim}
+ wxChar catalog[128+1];
+ wxChar schema[128+1];
+ wxChar tableName[DB_MAX_TABLE_NAME_LEN+1];
+ wxChar colName[DB_MAX_COLUMN_NAME_LEN+1];
+ SWORD sqlDataType;
+ wxChar typeName[128+1];
+ SWORD columnSize;
+ SWORD bufferLength;
+ short decimalDigits;
+ short numPrecRadix;
+ short nullable;
+ wxChar remarks[254+1];
+ int dbDataType; // conversion of the 'sqlDataType'
+ // to the generic data type used by
+ // these classes
+ int PkCol; // Primary key column
+ 0 = No
+ 1 = First Key
+ 2 = Second Key, etc...
+ wxChar PkTableName[DB_MAX_TABLE_NAME_LEN+1];
+ // Tables that use this PKey as a FKey
+ int FkCol; // Foreign key column
+ 0 = No
+ 1 = First Key
+ 2 = Second Key, etc...
+ wxChar FkTableName[DB_MAX_TABLE_NAME_LEN+1];
+ // Foreign key table name
+ wxDbColFor *pColFor; // How should this column be formatted
+\end{verbatim}
+
+The constructor for this class initializes all the values to zero, "", or NULL.
+
+The destructor for this class takes care of deleting the pColFor member if
+it is non-NULL.
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+\wxheading{Include files}
+
+<wx/db.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDbColInf::Initialize}\label{wxdbcolinfinitialize}
+
+Simply initializes all member variables to a cleared state. Called by
+the constructor automatically.
+
+\section{\class{wxDbConnectInf}}\label{wxdbconnectinf}
+
+This class is used for holding the data necessary for connecting to the ODBC
+datasource. That information includes: SQL environment handle, datasource
+name, user ID, password and default directory path (used with dBase). Other
+optional fields held in this class are and file type, both for future
+functions planned to be added for creating/manipulating datasource definitions.
+
+\membersection{wxDbConnectInf::wxDbConnectInf}\label{wxdbconnectinfctor}
+
+\func{}{wxDbConnectInf}{\void}
+
+Default constructor.
+
+\func{}{wxDbConnectInf}{\param{HENV }{henv}, \param{const wxString \&}{dsn},
+\param{const wxString \&}{userID=""}, \param{const wxString \&}{password},
+\param{const wxString \&}{defaultDir=""}, \param{const wxString \&}{description=""},
+\param{const wxString \&}{fileType=""}}
+
+Constructor which allows initial settings of all the classes member variables.
+
+See the special note below on the henv parameter for forcing this constructor
+to create a SQL environment handle automatically, rather than needing to pass
+one in to the function.
+
+\wxheading{Parameters}
+
+\docparam{henv}{Environment handle used for this connection. See\rtfsp
+\helpref{wxDConnectInf::AllocHenv}{wxdbconnectinfallochenv} for how to create
+an SQL environment handle. NOTE: Passing in a NULL for this parameter will
+inform the constructor that it should create its own SQL environment handle.
+If NULL is passed for this parameter, the constructor will call\rtfsp
+\helpref{wxDConnectInf::AllocHenv}{wxdbconnectinfallochenv} internally. A
+flag is set internally also to indicate that the HENV was created by the
+constructor so that when the default class destructor is called, the
+destructor will call \helpref{wxDConnectInf::FreeHenv}{wxdbconnectinffreehenv}\rtfsp
+to free the environment handle automatically.}
+\docparam{dsn}{Name of the datasource to be used in creating wxDb instances
+for creating connection(s) to a datasource.}
+\docparam{userID}{{\it OPTIONAL} Many datasources allow (or even require)
+use of a username to determine privileges that connecting user is allowed
+to have when accessing the datasource or the data tables. Default is "".}
+\docparam{password}{{\it OPTIONAL} Password to be associated with the user
+ID specified in 'userID'. Default is "".}
+\docparam{defaultDir}{{\it OPTIONAL} Used for datasources which require the
+path to where the data file is stored to be specified. dBase is one example
+of the type of datasource which requires this information. Default is "".}
+\docparam{description}{{\it OPTIONAL} {\bf FUTURE USE} Default is "".}
+\docparam{fileType}{{\it OPTIONAL} {\bf FUTURE USE} Default is "".}
+
+\wxheading{Remarks}
+
+It is strongly recommended that programs use the longer form of the
+constructor and allow the constructor to create the SQL environment handle
+automatically, and manage the destruction of the handle.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ wxDbConnectInf *DbConnectInf;
+
+ DbConnectInf = new wxDbConnectInf(0,"MY_DSN", "MY_USER", "MY_PASSWORD");
+
+ ....the rest of the program
+
+ delete DbConnectInf;
+\end{verbatim}
+
+\wxheading{See also}
+
+\helpref{wxDConnectInf::AllocHenv}{wxdbconnectinfallochenv},
+\helpref{wxDConnectInf::FreeHenv}{wxdbconnectinffreehenv}
+
+\membersection{wxDbConnectInf::\destruct{wxDbConnectInf}}\label{wxdbconnectinfdestr}
+
+\func{}{\destruct{wxDbConnectInf}}{}
+
+Handles the default destruction of the instance of the class. If the long form
+of the \helpref{wxDConnectInf}{wxdbconnectinf} was used, then this destructor
+also takes care of calling\rtfsp
+\helpref{wxDConnectInf::FreeHenv}{wxdbconnectinffreehenv} to free the
+SQL environment handle.
+
+\membersection{wxDbConnectInf::AllocHenv}\label{wxdbconnectinfallochenv}
+
+\func{bool }{AllocHenv}{\void}
+
+Allocates a SQL environment handle that will be used to interface with
+an ODBC datasource.
+
+\wxheading{Remarks}
+
+This function can be automatically called by the long from of the
+\helpref{wxDbConnectInf}{wxdbconnectinf} constructor.
+
+\membersection{wxDbConnectInf::FreeHenv}\label{wxdbconnectinffreehenv}
+
+\func{void}{FreeHenv}{\void}
+
+Frees the SQL environment handle being managed by the instance of this class.
+
+\wxheading{Remarks}
+
+If the SQL environment handle was created using the long form of the\rtfsp
+\helpref{wxDbConnectInf}{wxdbconnectinf} constructor, then the flag indicating
+that the HENV should be destroyed when the classes destructor is called
+is reset to be false, so that any future handles created using the\rtfsp
+\helpref{wxDbConnectInf::AllocHenv}{wxdbconnectinfallochenv} function
+must be manually released with a call to this function.
+
+\membersection{wxDbConnectInf::Initialize}\label{wxdbconnectinfinitialize}
+
+Simply initializes all member variables to a cleared state. Called by
+the constructor automatically.
+
+\membersection{wxDbConnectInf::GetAuthStr}\label{wxdbconnectinfgetauthstr}
+
+\func{const wxChar *}{GetAuthStr}{\void}
+
+Accessor function to return the password assigned for this class
+instance that will be used with the user ID.
+
+Synonymous with \helpref{wxDbConnectInf::GetPassword}{wxdbconnectinfgetpassword}
+
+\membersection{wxDbConnectInf::GetDefaultDir}\label{wxdbconnectinfgetdefaultdir}
+
+\func{const wxChar *}{GetDefaultDir}{\void}
+
+Accessor function to return the default directory in which the datasource's data
+table is stored. This directory is only used for file based datasources like
+dBase. MS-Access does not require this to be set, as the path is set in the
+ODBC Administrator for MS-Access.
+
+\membersection{wxDbConnectInf::GetDescription}\label{wxdbconnectinfgetdescription}
+
+\func{const wxChar *}{GetDescription}{\void}
+
+Accessor function to return the description assigned for this class
+instance.
+
+NOTE: Description is a FUTURE USE item and is unused currently.
+
+\membersection{wxDbConnectInf::GetDsn}\label{wxdbconnectinfgetdsn}
+
+\func{const wxChar *}{GetDsn}{\void}
+
+Accessor function to return the datasource name assigned for this class
+instance.
+
+\membersection{wxDbConnectInf::GetFileType}\label{wxdbconnectinfgetfiletype}
+
+\func{const wxChar *}{GetFileType}{\void}
+
+Accessor function to return the filetype of the ODBC datasource assigned for
+this class instance.
+
+NOTE: FileType is a FUTURE USE item and is unused currently.
+
+\membersection{wxDbConnectInf::GetHenv}\label{wxdbconnectinfgethenv}
+
+\func{const HENV}{GetHenv}{\void}
+
+Accessor function to return the SQL environment handle being managed
+by this class instance.
+
+\membersection{wxDbConnectInf::GetPassword}\label{wxdbconnectinfgetpassword}
+
+\func{const wxChar *}{GetPassword}{\void}
+
+Accessor function to return the password assigned for this class
+instance that will be used with the user ID.
+
+Synonymous with \helpref{wxDbConnectInf::GetAuthStr}{wxdbconnectinfgetauthstr}
+
+\membersection{wxDbConnectInf::GetUid}\label{wxdbconnectinfgetuid}
+
+\func{const wxChar *}{GetUid}{\void}
+
+Accessor function to return the user ID assigned for this class
+instance.
+
+\membersection{wxDbConnectInf::GetUserID}\label{wxdbconnectinfgetuserid}
+
+\func{const wxChar *}{GetUserID}{\void}
+
+Accessor function to return the user ID assigned for this class
+instance.
+
+\membersection{wxDbConnectInf::SetAuthStr}\label{wxdbconnectinfsetauthstr}
+
+\func{\void}{SetAuthStr}{const wxString \&authstr}
+
+Accessor function to assign the password for this class
+instance that will be used with the user ID.
+
+Synonymous with \helpref{wxDbConnectInf::SetPassword}{wxdbconnectinfsetpassword}
+
+\membersection{wxDbConnectInf::SetDefaultDir}\label{wxdbconnectinfsetdefaultdir}
+
+\func{\void}{SetDefaultDir}{const wxString \&defDir}
+
+Accessor function to assign the default directory in which the datasource's data
+table is stored. This directory is only used for file based datasources like
+dBase. MS-Access does not require this to be set, as the path is set in the
+ODBC Administrator for MS-Access.
+
+\membersection{wxDbConnectInf::SetDescription}\label{wxdbconnectinfsetdescription}
+
+\func{\void}{SetDescription}{const wxString \&desc}
+
+Accessor function to assign the description assigned for this class
+instance.
+
+NOTE: Description is a FUTURE USE item and is unused currently.
+
+\membersection{wxDbConnectInf::SetDsn}\label{wxdbconnectinfsetdsn}
+
+\func{\void}{SetDsn}{const wxString \&dsn}
+
+Accessor function to assign the datasource name for this class instance.
+
+\membersection{wxDbConnectInf::SetFileType}\label{wxdbconnectinfsetfiletype}
+
+\func{\void}{SetFileType}{const wxString \&}
+
+Accessor function to return the filetype of the ODBC datasource assigned for
+this class instance.
+
+NOTE: FileType is a FUTURE USE item and is unused currently.
+
+\membersection{wxDbConnectInf::SetHenv}\label{wxdbconnectinfsethenv}
+
+\func{void}{SetHenv}{\param{const HENV }{henv}}
+
+Accessor function to set the SQL environment handle for this class instance.
+
+\membersection{wxDbConnectInf::SetPassword}\label{wxdbconnectinfsetpassword}
+
+\func{\void}{SetPassword}{const wxString \&password}
+
+Accessor function to assign the password for this class
+instance that will be used with the user ID.
+
+Synonymous with \helpref{wxDbConnectInf::SetAuthStr}{wxdbconnectinfsetauthstr}
+
+\membersection{wxDbConnectInf::SetUid}\label{wxdbconnectinfsetuid}
+
+\func{\void}{SetUid}{const wxString \&uid}
+
+Accessor function to set the user ID for this class instance.
+
+\membersection{wxDbConnectInf::SetUserID}\label{wxdbconnectinfsetuserid}
+
+\func{\void}{SetUserID}{const wxString \&userID}
+
+Accessor function to assign the user ID for this class instance.
+
+\section{\class{wxDbIdxDef}}\label{wxdbidxdef}
+
+Used in creation of non-primary indexes. Currently there are no member
+functions for this class.
+
+\begin{verbatim}
+ wxChar ColName[DB_MAX_COLUMN_NAME_LEN+1]
+ // Name of column
+ bool Ascending // Is index maintained in
+ ASCENDING sequence?
+\end{verbatim}
+
+There are no constructors/destructors as of this time, and no member functions.
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+
+\wxheading{Include files}
+
+<wx/db.h>
+
+\section{\class{wxDbInf}}\label{wxdbinf}
+
+Contains information regarding the database connection (datasource name,
+number of tables, etc). A pointer to a wxDbTableInf is included in this
+class so a program can create a wxDbTableInf array instance to maintain all
+information about all tables in the datasource to have all the datasource's
+information in one memory structure.
+
+Primarily, this class is used internally by the wxWidgets ODBC classes.
+
+\begin{verbatim}
+ wxChar catalog[128+1];
+ wxChar schema[128+1]; // typically means owner of table(s)
+ int numTables; // How many tables does this
+ datasource have
+ wxDbTableInf *pTableInf; // Equals a new
+ wxDbTableInf[numTables];
+\end{verbatim}
+
+The constructor for this class initializes all the values to zero, "", or NULL.
+
+The destructor for this class takes care of deleting the pTableInf member if
+it is non-NULL.
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+\wxheading{Include files}
+
+<wx/db.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDbInf::Initialize}\label{wxdbinfinitialize}
+
+Simply initializes all member variables to a cleared state. Called by
+the constructor automatically.
+
+\section{\class{wxDbTable}}\label{wxdbtable}
+
+A wxDbTable instance provides re-usable access to rows of data in
+a table contained within the associated ODBC datasource
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+\wxheading{Include files}
+
+<wx/dbtable.h>\\
+<wx/db.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+\wxheading{Helper classes and data structures}
+
+The following classes and structs are defined in dbtable.cpp/.h for use
+with the wxDbTable class.
+
+\begin{itemize}\itemsep=0pt
+\item \helpref{wxDbColDef}{wxdbcoldef}
+\item \helpref{wxDbColDataPtr}{wxdbcoldataptr}
+\item \helpref{wxDbIdxDef}{wxdbidxdef}
+\end{itemize}
+
+\wxheading{Constants}
+
+\begin{verbatim}
+ wxDB_DEFAULT_CURSOR Primary cursor normally used for cursor based
+ operations.
+
+ wxDB_QUERY_ONLY Used to indicate whether a table that is opened
+ is for query only, or if insert/update/deletes
+ will be performed on the table. Less overhead
+ (cursors and memory) are allocated for query
+ only tables, plus read access times are faster
+ with some datasources.
+
+ wxDB_ROWID_LEN [Oracle only] - Used when CanUpdateByRowID()
+ is true. Optimizes updates so they are faster
+ by updating on the Oracle-specific ROWID column
+ rather than some other index.
+
+
+ wxDB_DISABLE_VIEW Use to indicate when a database view should not
+ be if a table is normally set up to use a view.
+ [Currently unsupported.]
+
+\end{verbatim}
+
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDbTable::wxDbTable}\label{wxdbtableconstr}
+
+\func{}{wxDbTable}{\param{wxDb *}{pwxDb}, \param{const wxString \&}{tblName},
+ \param{const UWORD }{numColumns}, \param{const wxString \&}{qryTblName = ""},
+ \param{bool }{qryOnly = !wxDB\_QUERY\_ONLY}, \param{const wxString \&}{tblPath = ""}}
+
+Default constructor.
+
+\wxheading{Parameters}
+
+\docparam{pwxDb}{Pointer to the wxDb instance to be used by this wxDbTable
+instance.}
+\docparam{tblName}{The name of the table in the RDBMS.}
+\docparam{numColumns}{The number of columns in the table. (Do NOT include the ROWID
+column in the count if using Oracle).}
+\docparam{qryTblName}{{\it OPTIONAL}. The name of the table or view to base
+your queries on. This argument allows you to specify a table/view other than
+the base table for this object to base your queries on. This allows you to
+query on a view for example, but all of the INSERT, UPDATE and DELETES will
+still be performed on the base table for this wxDbTable object. Basing your
+queries on a view can provide a substantial performance increase in cases where
+your queries involve many tables with multiple joins. Default is "".}
+\docparam{qryOnly}{{\it OPTIONAL}. Indicates whether the table will be
+accessible for query purposes only, or should the table create the necessary
+cursors to be able to insert, update, and delete data from the table.
+Default is !wxDB\_QUERY\_ONLY.}
+\docparam{tblPath}{{\it OPTIONAL}. Some datasources (such as dBase)
+require a path to where the table is stored on the system. Default is "".}
+
+\membersection{wxDbTable::wxDbTable}\label{wxdbtabledestr}
+
+\func{virtual}{\destruct{wxDbTable}}{}
+
+Virtual default destructor.
+
+\membersection{wxDbTable::BuildDeleteStmt}\label{wxdbtablebuilddeletestmt}
+
+\func{void}{BuildDeleteStmt}{\param{wxString \&}{pSqlStmt},
+\param{int }{typeOfDel}, \param{const wxString \&}{pWhereClause=""}}
+
+Constructs the full SQL statement that can be used to delete all rows matching
+the criteria in the pWhereClause.
+
+\wxheading{Parameters}
+
+\docparam{pSqlStmt}{Pointer to buffer for the SQL statement retrieved. To be
+sure you have adequate space allocated for the SQL statement, allocate
+DB\_MAX\_STATEMENT\_LEN bytes.}
+\docparam{typeOfDel}{The type of delete statement being performed. Can be one
+of three values: DB\_DEL\_KEYFIELDS, DB\_DEL\_WHERE or DB\_DEL\_MATCHING}
+\docparam{pWhereClause}{{\it OPTIONAL}. If the typeOfDel is DB\_DEL\_WHERE,
+then you must also pass in a SQL WHERE clause in this argument. Default
+is "".}
+
+\wxheading{Remarks}
+
+This member function constructs a SQL DELETE statement. This can be used for
+debugging purposes if you are having problems executing your SQL statement.
+
+WHERE and FROM clauses specified using \helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+and \helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} are ignored by
+this function.
+
+\membersection{wxDbTable::BuildSelectStmt}\label{wxdbtablebuildselectstmt}
+
+\func{void}{BuildSelectStmt}{\param{wxString \&}{pSqlStmt},
+\param{int }{typeOfSelect}, \param{bool }{distinct}}
+
+Constructs the full SQL statement that can be used to select all rows matching
+the criteria in the pWhereClause. This function is called internally in the
+wxDbTable class whenever the function \helpref{wxDbTable::Query}{wxdbtablequery}
+is called.
+
+NOTE: Only the columns specified in \helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs}
+statements are included in the list of columns returned by the SQL statement
+created by a call to this function.
+
+\wxheading{Parameters}
+
+\docparam{pSqlStmt}{Pointer to storage for the SQL statement retrieved. To be
+sure you have adequate space allocated for the SQL statement, allocate
+DB\_MAX\_STATEMENT\_LEN bytes.}
+\docparam{typeOfSelect}{The type of select statement being performed. Can be
+one of four values: DB\_SELECT\_KEYFIELDS, DB\_SELECT\_WHERE, DB\_SELECT\_MATCHING
+or DB\_SELECT\_STATEMENT.}
+\docparam{distinct}{Whether to select distinct records only.}
+
+\wxheading{Remarks}
+
+This member function constructs a SQL SELECT statement. This can be used for
+debugging purposes if you are having problems executing your SQL statement.
+
+WHERE and FROM clauses specified using
+\helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+and \helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} are ignored by
+this function.
+
+\membersection{wxDbTable::BuildUpdateStmt}\label{wxdbtablebuildupdatestmt}
+
+\func{void}{BuildUpdateStmt}{\param{wxString \&}{pSqlStmt}, \param{int }{typeOfUpd},
+\param{const wxString \&}{pWhereClause=""}}
+
+Constructs the full SQL statement that can be used to update all rows matching
+the criteria in the pWhereClause.
+
+If typeOfUpdate is DB\_UPD\_KEYFIELDS, then the current values in the bound columns
+are used to determine which row(s) in the table are to be updated. The
+exception to this is when a datasource supports ROW IDs (Oracle). The ROW ID
+column is used for efficiency purposes when available.
+
+NOTE: Only the columns specified in \helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs}
+statements are included in the list of columns updated by the SQL statement
+created by a call to this function. Any column definitions that were defined
+as being non-updateable will be excluded from the SQL UPDATE statement created
+by this function.
+
+\wxheading{Parameters}
+
+\docparam{pSqlStmt}{Pointer to storage for the SQL statement retrieved. To be
+sure you have adequate space allocated for the SQL statement, allocate
+DB\_MAX\_STATEMENT\_LEN bytes.}
+\docparam{typeOfUpdate}{The type of update statement being performed. Can be one
+of two values: DB\_UPD\_KEYFIELDS or DB\_UPD\_WHERE.}
+\docparam{pWhereClause}{{\it OPTIONAL}. If the typeOfUpdate is DB\_UPD\_WHERE,
+then you must also pass in a SQL WHERE clause in this argument. Default is "".}
+
+\wxheading{Remarks}
+
+This member function allows you to see what the SQL UPDATE statement looks like
+that the ODBC class library builds. This can be used for debugging purposes if
+you are having problems executing your SQL statement.
+
+WHERE and FROM clauses specified using \helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+and \helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} are ignored by
+this function.
+
+
+\membersection{wxDbTable::BuildWhereClause}\label{wxdbtablebuildwhereclause}
+
+\func{void}{BuildWhereClause}{\param{wxString \&}{pWhereClause},
+\param{int }{typeOfWhere}, \param{const wxString \&}{qualTableName=""},
+\param{bool }{useLikeComparison=false}}
+
+Constructs the portion of a SQL statement which would follow the word 'WHERE'
+in a SQL statement to be passed to the datasource. The returned string
+does NOT include the word 'WHERE'.
+
+\wxheading{Parameters}
+
+\docparam{pWhereClause}{Pointer to storage for the SQL statement retrieved.
+To be sure you have adequate space allocated for the SQL statement, allocate
+DB\_MAX\_STATEMENT\_LEN bytes.}
+\docparam{typeOfWhere}{The type of where clause to generate. Can be one of
+two values: DB\_WHERE\_KEYFIELDS or DB\_WHERE\_MATCHING.}
+\docparam{qualTableName}{{\it OPTIONAL}. Prepended to all base table
+column names. For use when a FROM clause has been specified with the
+\helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause},
+to clarify which table a column name reference belongs to. Default is "".}
+\docparam{useLikeComparison}{{\it OPTIONAL}. Should the constructed WHERE
+clause utilize the LIKE comparison operator. If false, then the '='
+operator is used. Default is false.}
+
+\wxheading{Remarks}
+
+This member function allows you to see what the SQL WHERE clause looks like
+that the ODBC class library builds. This can be used for debugging purposes
+if you are having problems executing your own SQL statements.
+
+If using 'typeOfWhere' set to DB\_WHERE\_MATCHING, any bound columns currently
+containing a NULL value are not included in the WHERE clause's list of
+columns to use in the comparison.
+
+
+\membersection{wxDbTable::CanSelectForUpdate}\label{wxdbtablecanselectforupdate}
+
+\func{bool}{CanSelectForUpdate}{\void}
+
+Use this function to determine if the datasource supports SELECT ... FOR UPDATE.
+When the keywords "FOR UPDATE" are included as part of your SQL SELECT statement,
+all records {\it retrieved} (not just queried, but actually retrieved using
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext}, etc) from the result set are
+locked.
+
+\wxheading{Remarks}
+
+Not all datasources support the "FOR UPDATE" clause, so you must use this
+member function to determine if the datasource currently connected to supports
+this behavior or not before trying to select using "FOR UPDATE".
+
+If the wxDbTable instance was created with the parameter wxDB\_QUERY\_ONLY, then
+this function will return false. For all known databases which do not support
+the FOR UPDATE clause, this function will return false also.
+
+\membersection{wxDbTable::CanUpdateByROWID}\label{wxdbtablecanupdatebyrowid}
+
+\func{bool}{CanUpdateByROWID}{\void}
+
+CURRENTLY ONLY POSSIBLE IF USING ORACLE.
+
+--- CURRENTLY DISABLED FOR *ALL* DATASOURCES --- NOV 1 2000 - gt
+
+Every Oracle table has a hidden column named ROWID. This is a pointer to the
+physical location of the record in the datasource and allows for very fast
+updates and deletes. The key is to retrieve this ROWID during your query so
+it is available during an update or delete operation.
+
+Use of the ROWID feature is always handled by the class library except in the
+case of \helpref{wxDbTable::QueryBySqlStmt}{wxdbtablequerybysqlstmt}. Since
+you are passing in the SQL SELECT statement,
+it is up to you to include the ROWID column in your query. If you do not,
+the application will still work, but may not be as optimized. The ROWID is
+always the last column in the column list in your SQL SELECT statement.
+The ROWID is not a column in the normal sense and should not be considered
+part of the column definitions for the wxDbTable object.
+
+\wxheading{Remarks}
+
+The decision to include the ROWID in your SQL SELECT statement must be
+deferred until runtime since it depends on whether you are connected
+to an Oracle datasource or not.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Incomplete code sample
+ wxDbTable parts;
+ .....
+ if (parts.CanUpdateByROWID())
+ {
+ // Note that the ROWID column must always be the last column selected
+ sqlStmt = "SELECT PART_NUM, PART_DESC, ROWID" FROM PARTS";
+ }
+ else
+ sqlStmt = "SELECT PART_NUM, PART_DESC FROM PARTS";
+\end{verbatim}
+
+
+\membersection{wxDbTable::ClearMemberVar}\label{wxdbtableclearmembervar}
+
+\func{void}{ClearMemberVar}{\param{UWORD }{colNumber}, \param{bool }{setToNull=false}}
+
+Same as \helpref{wxDbTable::ClearMemberVars}{wxdbtableclearmembervars} except
+that this function clears only the specified column of its values, and
+optionally sets the column to be a NULL column.
+
+\docparam{colNumber}{Column number that is to be cleared. This number (between 0
+and (numColumns-1)) is the index of the column definition created using the
+\helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs} function.}
+\docparam{setToNull}{{\it OPTIONAL}. Indicates whether the column should be
+flagged as being a NULL value stored in the bound memory variable. If true,
+then any value stored in the bound member variable is cleared. Default is
+false.}
+
+\membersection{wxDbTable::ClearMemberVars}\label{wxdbtableclearmembervars}
+
+\func{void}{ClearMemberVars}{\param{bool }{setToNull=false}}
+
+Initializes all bound columns of the wxDbTable instance to zero. In the case
+of a string, zero is copied to the first byte of the string.
+
+\docparam{setToNull}{{\it OPTIONAL}. Indicates whether all columns should be
+flagged as having a NULL value stored in the bound memory variable. If true,
+then any value stored in the bound member variable is cleared. Default is
+false.}
+
+\wxheading{Remarks}
+
+This is useful before calling functions such as
+\helpref{wxDbTable::QueryMatching}{wxdbtablequerymatching} or
+\helpref{wxDbTable::DeleteMatching}{wxdbtabledeletematching} since these
+functions build their WHERE clauses from non-zero columns. To call either
+\helpref{wxDbTable::QueryMatching}{wxdbtablequerymatching} or
+\helpref{wxDbTable::DeleteMatching}{wxdbtabledeletematching} use this sequence:
+
+\begin{verbatim}
+1) ClearMemberVars()
+2) Assign columns values you wish to match on
+3) Call wxDbTable::QueryMatching() or wxDbTable::DeleteMatching()
+\end{verbatim}
+
+\membersection{wxDbTable::CloseCursor}\label{wxdbtableclosecursor}
+
+\func{bool}{CloseCursor}{\param{HSTMT}{cursor}}
+
+Closes the specified cursor associated with the wxDbTable object.
+
+\wxheading{Parameters}
+
+\docparam{cursor}{The cursor to be closed.}
+
+\wxheading{Remarks}
+
+Typically handled internally by the ODBC class library, but may be used by the
+programmer if desired.
+
+\normalbox{DO NOT CLOSE THE wxDB\_DEFAULT\_CURSOR!}
+
+\membersection{wxDbTable::Count}\label{wxdbtablecount}
+
+\func{ULONG }{Count}{\param{const wxString \&}{args="*"}}
+
+Returns the number of records which would be in the result set using the
+current query parameters specified in the WHERE and FROM clauses.
+
+\wxheading{Parameters}
+
+\docparam{args}{{\it OPTIONAL}. This argument allows the use of the
+DISTINCT keyword against a column name to cause the returned count to
+only indicate the number of rows in the result set that have a unique
+value in the specified column. An example is shown below. Default is "*",
+meaning a count of the total number of rows matching is returned, regardless
+of uniqueness.}
+
+\wxheading{Remarks}
+
+This function can be called before or after an actual query to obtain the
+count of records in the result set. Count() uses its own cursor, so result
+set cursor positioning is not affected by calls to Count().
+
+WHERE and FROM clauses specified using
+\helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+and \helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} ARE used by
+this function.
+
+\wxheading{Example}
+
+\begin{verbatim}
+
+ USERS TABLE
+
+ FIRST_NAME LAST_NAME
+ ----------- ----------
+ John Doe
+ Richard Smith
+ Michael Jones
+ John Carpenter
+
+ // Incomplete code sample
+ wxDbTable users;
+ .....
+ users.SetWhereClause("");
+
+ // This Count() will return 4, as there are four users listed above
+ // that match the query parameters
+ totalNumberOfUsers = users.Count();
+
+ // This Count() will return 3, as there are only 3 unique first names
+ // in the table above - John, Richard, Michael.
+ totalNumberOfUniqueFirstNames = users.Count("DISTINCT FIRST_NAME");
+\end{verbatim}
+
+\membersection{wxDbTable::CreateIndex}\label{wxdbtablecreateindex}
+
+\func{bool}{CreateIndex}{\param{const wxString \&}{IndexName}, \param{bool }{unique},
+\param{UWORD }{numIndexColumns}, \param{wxDbIdxDef *}{pIndexDefs},
+\param{bool }{attemptDrop=true}}
+
+This member function allows you to create secondary (non-primary) indexes on
+your tables. You first create your table, normally specifying a primary
+index, and then create any secondary indexes on the table. Indexes in
+relational model are not required. You do not need indexes to look up records
+in a table or to join two tables together. In the relational model, indexes,
+if available, provide a quicker means to look up data in a table. To enjoy
+the performance benefits of indexes, the indexes must be defined on the
+appropriate columns and your SQL code must be written in such a way as to
+take advantage of those indexes.
+
+\wxheading{Parameters}
+
+\docparam{IndexName}{Name of the Index. Name must be unique within the table
+space of the datasource.}
+\docparam{unique}{Indicates if this index is unique.}
+\docparam{numIndexColumns}{Number of columns in the index.}
+\docparam{pIndexDefs}{A pointer to an array \helpref{wxDbIdxDef}{wxdbidxdef} structures. }
+\docparam{attemptDrop}{{\it OPTIONAL}. Indicates if the function should try
+to execute a \helpref{wxDbTable::DropIndex}{wxdbtabledropindex} on the index
+name provided before trying to create the index name. Default is true.}
+
+\wxheading{Remarks}
+
+The first parameter, index name, must be unique and should be given a
+meaningful name. Common practice is to include the table name as a prefix
+in the index name (e.g. For table PARTS, you might want to call your index
+PARTS\_Index1). This will allow you to easily view all
+of the indexes defined for a given table grouped together alphabetically.
+
+The second parameter indicates if the index is unique or not. Uniqueness
+is enforced at the RDBMS level preventing rows which would have duplicate
+indexes from being inserted into the table when violating a unique index's
+uniqueness.
+
+In the third parameter, specify how many columns are in your index. This
+number must match the number of columns defined in the 'pIndexDefs' parameter.
+
+The fourth parameter specifies which columns make up the index using the
+\helpref{wxDbIdxDef}{wxdbidxdef} structure. For each column in the index, you must specify two
+things, the column name and the sort order (ascending / descending). See
+the example below to see how to build and pass in the \helpref{wxDbIdxDef}{wxdbidxdef} structure.
+
+The fifth parameter is provided to handle the differences in datasources as
+to whether they will automatically overwrite existing indexes with the same
+name or not. Some datasources require that the existing index must be dropped
+first, so this is the default behavior.
+
+Some datasources (MySQL, and possibly others) require columns which are to be
+part of an index to be defined as NOT NULL. When this function is called, if
+a column is not defined to be NOT NULL, a call to this function will modify
+the column definition to change any columns included in the index to be
+NOT NULL. In this situation, if a NULL value already exists in one of the
+columns that is being modified, creation of the index will fail.
+
+PostGres is unable to handle index definitions which specify whether the index
+is ascending or descending, and defaults to the system default when the index
+is created.
+
+It is not necessary to call \helpref{wxDb::CommitTrans}{wxdbcommittrans}
+after executing this function.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Create a secondary index on the PARTS table
+ wxDbIdxDef IndexDef[2]; // 2 columns make up the index
+
+ wxStrcpy(IndexDef[0].ColName, "PART_DESC"); // Column 1
+ IndexDef[0].Ascending = true;
+
+ wxStrcpy(IndexDef[1].ColName, "SERIAL_NO"); // Column 2
+ IndexDef[1].Ascending = false;
+
+ // Create a name for the index based on the table's name
+ wxString indexName;
+ indexName.Printf("%s_Index1",parts->GetTableName());
+ parts->CreateIndex(indexName, true, 2, IndexDef);
+\end{verbatim}
+
+\membersection{wxDbTable::CreateTable}\label{wxdbtablecreatetable}
+
+\func{bool}{CreateTable}{\param{bool }{attemptDrop=true}}
+
+Creates a table based on the definitions previously defined for this
+wxDbTable instance.
+
+\wxheading{Parameters}
+
+\docparam{attemptDrop}{{\it OPTIONAL}. Indicates whether the driver should
+attempt to drop the table before trying to create it. Some datasources will
+not allow creation of a table if the table already exists in the table space
+being used. Default is true.}
+
+\wxheading{Remarks}
+
+This function creates the table and primary index (if any) in the table space
+associated with the connected datasource. The owner of these objects will
+be the user id that was given when \helpref{wxDb::Open}{wxdbopen} was called.
+The objects will be created in the default schema/table space for that user.
+
+In your derived wxDbTable object constructor, the columns and primary index
+of the table are described through the \helpref{wxDbColDef}{wxdbcoldef} structure.
+\helpref{wxDbTable::CreateTable}{wxdbtablecreatetable} uses this information
+to create the table and to add the primary index. See
+\helpref{wxDbTable}{wxdbtable} ctor and wxDbColDef description for additional
+information on describing the columns of the table.
+
+It is not necessary to call \helpref{wxDb::CommitTrans}{wxdbcommittrans}
+after executing this function.
+
+\membersection{wxDbTable::DB\_STATUS}\label{wxdbtabledbstatus}
+
+\func{bool}{DB\_STATUS}{\void}
+
+Accessor function that returns the wxDb private member variable DB\_STATUS for
+the database connection used by this instance of wxDbTable.
+
+\membersection{wxDbTable::Delete}\label{wxdbtabledelete}
+
+\func{bool}{Delete}{\void}
+
+Deletes the row from the table indicated by the current cursor.
+
+\wxheading{Remarks}
+
+Use \helpref{wxDbTable::GetFirst}{wxdbtablegetfirst},
+\helpref{wxDbTable::GetLast}{wxdbtablegetlast},
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext} or
+\helpref{wxDbTable::GetPrev}{wxdbtablegetprev} to position the cursor to
+a valid record. Once positioned on a record, call this function to delete
+the row from the table.
+
+A \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans} must be called after use of
+this function to commit or rollback the deletion.
+
+NOTE: Most datasources have a limited size "rollback" segment. This means
+that it is only possible to insert/update/delete a finite number of rows
+without performing a \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans}. Size of the rollback
+segment varies from database to database, and is user configurable in
+most databases. Therefore it is usually best to try to perform a commit
+or rollback at relatively small intervals when processing a larger number
+of actions that insert/update/delete rows in a table.
+
+\membersection{wxDbTable::DeleteCursor}\label{wxdbtabledeletecursor}
+
+\func{bool}{DeleteCursor}{\param{HSTMT *}{hstmtDel}}
+
+Allows a program to delete a cursor.
+
+\wxheading{Parameters}
+
+\docparam{hstmtDel}{Handle of the cursor to delete.}
+
+\wxheading{Remarks}
+
+For default cursors associated with the instance of wxDbTable, it is not
+necessary to specifically delete the cursors. This is automatically done
+in the wxDbTable destructor.
+
+NOTE: If the cursor could not be deleted for some reason, an error is logged
+indicating the reason. Even if the cursor could not be deleted, the HSTMT
+that is passed in is deleted, and the pointer is set to NULL.
+
+\normalbox{DO NOT DELETE THE wxDB\_DEFAULT\_CURSOR!}
+
+\membersection{wxDbTable::DeleteMatching}\label{wxdbtabledeletematching}
+
+\func{bool}{DeleteMatching}{\void}
+
+This member function allows you to delete records from your wxDbTable object
+by specifying the data in the columns to match on.
+
+\wxheading{Remarks}
+
+To delete all users with a first name of "JOHN", do the following:
+
+\begin{enumerate}\itemsep=0pt
+\item Clear all "columns" using wxDbTable::ClearMemberVars().
+\item Set the FIRST\_NAME column equal to "JOHN".
+\item Call wxDbTable::DeleteMatching().
+\end{enumerate}
+
+The WHERE clause is built by the ODBC class library based on all non-NULL
+columns. This allows deletion of records by matching on any column(s) in
+your wxDbTable instance, without having to write the SQL WHERE clause.
+
+A \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans} must be called after use of
+this function to commit or rollback the deletion.
+
+NOTE: Row(s) should be locked before deleting them to make sure they are
+not already in use. This can be achieved by calling
+\helpref{wxDbTable::QueryMatching}{wxdbtablequerymatching},
+and then retrieving the records, locking each as you go (assuming FOR UPDATE
+is allowed on the datasource). After the row(s) have been successfully locked,
+call this function.
+
+NOTE: Most datasources have a limited "rollback" segment. This means
+that it is only possible to insert/update/delete a finite number of rows
+without performing a \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans}. Size of the rollback
+segment varies from database to database, and is user configurable in
+most databases. Therefore it is usually best to try to perform a commit
+or rollback at relatively small intervals when processing a larger number
+of actions that insert/update/delete rows in a table.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Incomplete code sample to delete all users with a first name
+ // of "JOHN"
+ users.ClearMemberVars();
+ wxStrcpy(users.FirstName,"JOHN");
+ users.DeleteMatching();
+\end{verbatim}
+
+
+\membersection{wxDbTable::DeleteWhere}\label{wxdbtabledeletewhere}
+
+\func{bool}{DeleteWhere}{\param{const wxString \&}{pWhereClause}}
+
+Deletes all rows from the table which match the criteria specified in the
+WHERE clause that is passed in.
+
+\wxheading{Parameters}
+
+\docparam{pWhereClause}{SQL WHERE clause. This WHERE clause determines which
+records will be deleted from the table interfaced through the wxDbTable
+instance. The WHERE clause passed in must be compliant with the SQL 92
+grammar. Do not include the keyword 'WHERE'
+}
+
+\wxheading{Remarks}
+
+This is the most powerful form of the wxDbTable delete functions. This
+function gives access to the full power of SQL. This function can be used
+to delete records by passing a valid SQL WHERE clause. Sophisticated
+deletions can be performed based on multiple criteria using the full
+functionality of the SQL language.
+
+A \helpref{wxDb::CommitTrans}{wxdbcommittrans} must be called after use of
+this function to commit the deletions.
+
+Note: This function is limited to deleting records from the table associated
+with this wxDbTable object only. Deletions on joined tables is not possible.
+
+NOTE: Most datasources have a limited size "rollback" segment. This means
+that it is only possible to insert/update/delete a finite number of rows
+without performing a \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans}. Size of the rollback
+segment varies from database to database, and is user configurable in
+most databases. Therefore it is usually best to try to perform a commit
+or rollback at relatively small intervals when processing a larger number
+of actions that insert/update/delete rows in a table.
+
+WHERE and FROM clauses specified using \helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+and \helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} are ignored by
+this function.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Delete parts 1 thru 10 from containers 'X', 'Y' and 'Z' that
+ // are magenta in color
+ parts.DeleteWhere("(PART_NUMBER BETWEEN 1 AND 10) AND \
+ CONTAINER IN ('X', 'Y', 'Z') AND \
+ UPPER(COLOR) = 'MAGENTA'");
+\end{verbatim}
+
+
+\membersection{wxDbTable::DropIndex}\label{wxdbtabledropindex}
+
+\func{bool}{DropIndex}{\param{const wxString \&}{IndexName}}
+
+Allows an index on the associated table to be dropped (deleted) if the user
+login has sufficient privileges to do so.
+
+\wxheading{Parameters}
+
+\docparam{IndexName}{Name of the index to be dropped.}
+
+\wxheading{Remarks}
+
+If the index specified in the 'IndexName' parameter does not exist, an error
+will be logged, and the function will return a result of false.
+
+It is not necessary to call \helpref{wxDb::CommitTrans}{wxdbcommittrans}
+after executing this function.
+
+\membersection{wxDbTable::DropTable}\label{wxdbtabledroptable}
+
+\func{bool}{DropTable}{\void}
+
+Deletes the associated table if the user has sufficient privileges to do so.
+
+\wxheading{Remarks}
+
+This function returns true if the table does not exist, but only for
+supported databases (see \helpref{wxDb::Dbms}{wxdbdbms}). If a datasource
+is not specifically supported, and this function is called, the function
+will return false.
+
+Most datasources/ODBC drivers will delete any indexes associated with the
+table automatically, and others may not. Check the documentation for your
+database to determine the behavior.
+
+It is not necessary to call \helpref{wxDb::CommitTrans}{wxdbcommittrans}
+after executing this function.
+
+\membersection{wxDbTable::From}\label{wxdbtablefrom}
+
+\func{const wxString \&}{From}{}
+
+\func{void}{From}{\param{const wxString \&}{From}}
+
+Accessor function for the private class member wxDbTable::from. Can be used
+as a synonym for \helpref{wxDbTable::GetFromClause}{wxdbtablegetfromclause}
+(the first form of this function) or
+\helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} (the second form
+of this function).
+
+\wxheading{Parameters}
+
+\docparam{From}{A comma separated list of table names that are to be inner
+joined with the base table's columns so that the joined table's columns
+may be returned in the result set or used as a portion of a comparison with
+the base table's columns. NOTE that the base tables name must NOT be included
+in the FROM clause, as it is automatically included by the wxDbTable class
+in constructing query statements.}
+
+\wxheading{Return value}
+
+The first form of this function returns the current value of the wxDbTable
+member variable ::from.
+
+The second form of the function has no return value, as it will always set
+the from clause successfully.
+
+\wxheading{See also}
+
+\helpref{wxDbTable::GetFromClause}{wxdbtablegetfromclause},
+\helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause}
+
+
+\membersection{wxDbTable::GetColDefs}\label{wxdbtablegetcoldefs}
+
+\func{wxDbColDef *}{GetColDefs}{}
+
+Accessor function that returns a pointer to the array of column definitions
+that are bound to the columns that this wxDbTable instance is associated
+with.
+
+To determine the number of elements pointed to by the returned
+\helpref{wxDbColDef}{wxdbcoldef} pointer, use the
+\helpref{wxDbTable::GetNumberOfColumns}{wxdbtablegetnumberofcolumns} function.
+
+\wxheading{Remarks}
+
+These column definitions must not be manually redefined after they have been
+set.
+
+\membersection{wxDbTable::GetCursor}\label{wxdbtablegetcursor}
+
+\func{HSTMT}{GetCursor}{\void}
+
+Returns the HSTMT value of the current cursor for this wxDbTable object.
+
+\wxheading{Remarks}
+
+This function is typically used just before changing to use a different cursor
+so that after the program is finished using the other cursor, the current
+cursor can be set back to being the cursor in use.
+
+\wxheading{See also}
+
+\helpref{wxDbTable::SetCursor}{wxdbtablesetcursor}, \helpref{wxDbTable::GetNewCursor}{wxdbtablegetnewcursor}
+
+\membersection{wxDbTable::GetDb}\label{wxdbtablegetdb}
+
+\func{wxDb *}{GetDb}{}
+
+Accessor function for the private member variable pDb which is a pointer to
+the datasource connection that this wxDbTable instance uses.
+
+\membersection{wxDbTable::GetFirst}\label{wxdbtablegetfirst}
+
+\func{bool}{GetFirst}{\void}
+
+Retrieves the FIRST row in the record set as defined by the current query.
+Before retrieving records, a query must be performed using
+\helpref{wxDbTable::Query}{wxdbtablequery},
+\helpref{wxDbTable::QueryOnKeyFields}{wxdbtablequeryonkeyfields},
+\helpref{wxDbTable::QueryMatching}{wxdbtablequerymatching} or
+\helpref{wxDbTable::QueryBySqlStmt}{wxdbtablequerybysqlstmt}.
+
+\wxheading{Remarks}
+
+This function can only be used if the datasource connection used by the
+wxDbTable instance was created with FwdOnlyCursors set to false. If the
+connection does not allow backward scrolling cursors, this function will
+return false, and the data contained in the bound columns will be undefined.
+
+\wxheading{See also}
+
+\helpref{wxDb::IsFwdOnlyCursors}{wxdbisfwdonlycursors}
+
+\membersection{wxDbTable::GetFromClause}\label{wxdbtablegetfromclause}
+
+\func{const wxString \&}{GetFromClause}{}
+
+Accessor function that returns the current FROM setting assigned with the
+\helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause}.
+
+\wxheading{See also}
+
+\helpref{wxDbTable::From}{wxdbtablefrom}
+
+\membersection{wxDbTable::GetLast}\label{wxdbtablegetlast}
+
+\func{bool}{GetLast}{\void}
+
+Retrieves the LAST row in the record set as defined by the current query.
+Before retrieving records, a query must be performed using
+\helpref{wxDbTable::Query}{wxdbtablequery},
+\helpref{wxDbTable::QueryOnKeyFields}{wxdbtablequeryonkeyfields},
+\helpref{wxDbTable::QueryMatching}{wxdbtablequerymatching} or
+\helpref{wxDbTable::QueryBySqlStmt}{wxdbtablequerybysqlstmt}.
+
+\wxheading{Remarks}
+
+This function can only be used if the datasource connection used by the
+wxDbTable instance was created with FwdOnlyCursors set to false. If the
+connection does not allow backward scrolling cursors, this function will
+return false, and the data contained in the bound columns will be undefined.
+
+\wxheading{See also}
+
+\helpref{wxDb::IsFwdOnlyCursors}{wxdbisfwdonlycursors}
+
+\membersection{wxDbTable::GetNewCursor}\label{wxdbtablegetnewcursor}
+
+\func{HSTMT *}{GetNewCursor}{\param{bool }{setCursor=false},
+\param{bool }{bindColumns=true}}
+
+This function will create a new cursor that can be used to access the table
+being referenced by this wxDbTable instance, or to execute direct SQL commands
+on without affecting the cursors that are already defined and possibly
+positioned.
+
+\wxheading{Parameters}
+
+\docparam{setCursor}{{\it OPTIONAL}. Should this new cursor be set to be the
+current cursor after successfully creating the new cursor. Default is false.}
+\docparam{bindColumns}{{\it OPTIONAL}. Should this new cursor be bound to all
+the memory variables that the default cursor is bound to. Default is true.}
+
+\wxheading{Remarks}
+
+This new cursor must be closed using
+\helpref{wxDbTable::DeleteCursor}{wxdbtabledeletecursor}
+by the calling program before the wxDbTable instance is deleted, or both
+memory and resource leaks will occur.
+
+\membersection{wxDbTable::GetNext}\label{wxdbtablegetnext}
+
+\func{bool}{GetNext}{\void}
+
+Retrieves the NEXT row in the record set after the current cursor position
+as defined by the current query. Before retrieving records, a query must be
+performed using \helpref{wxDbTable::Query}{wxdbtablequery},
+\helpref{wxDbTable::QueryOnKeyFields}{wxdbtablequeryonkeyfields},
+\helpref{wxDbTable::QueryMatching}{wxdbtablequerymatching} or
+\helpref{wxDbTable::QueryBySqlStmt}{wxdbtablequerybysqlstmt}.
+
+\wxheading{Return value}
+
+This function returns false when the current cursor has reached the end of
+the result set. When false is returned, data in the bound columns is
+undefined.
+
+\wxheading{Remarks}
+
+This function works with both forward and backward scrolling cursors.
+
+\wxheading{See also}
+\helpref{wxDbTable::++}{wxdbtableplusplus}
+
+\membersection{wxDbTable::GetNumberOfColumns}\label{wxdbtablegetnumberofcolumns}
+
+\func{UWORD }{GetNumberOfColumns}{}
+
+Accessor function that returns the number of columns that are statically
+bound for access by the wxDbTable instance.
+
+\membersection{wxDbTable::GetOrderByClause}\label{wxdbtablegetorderbyclause}
+
+\func{const wxString \&}{GetOrderByClause}{}
+
+Accessor function that returns the current ORDER BY setting assigned with
+the \helpref{wxDbTable::SetOrderByClause}{wxdbtablesetorderbyclause}.
+
+\wxheading{See also}
+
+\helpref{wxDbTable::OrderBy}{wxdbtableorderby}
+
+\membersection{wxDbTable::GetPrev}\label{wxdbtablegetprev}
+
+\func{bool}{GetPrev}{\void}
+
+Retrieves the PREVIOUS row in the record set before the current cursor
+position as defined by the current query. Before retrieving records, a
+query must be performed using \helpref{wxDbTable::Query}{wxdbtablequery},
+\helpref{wxDbTable::QueryOnKeyFields}{wxdbtablequeryonkeyfields},
+\helpref{wxDbTable::QueryMatching}{wxdbtablequerymatching} or
+\helpref{wxDbTable::QueryBySqlStmt}{wxdbtablequerybysqlstmt}.
+
+\wxheading{Return value}
+
+This function returns false when the current cursor has reached the beginning
+of the result set and there are now other rows prior to the cursors current
+position. When false is returned, data in the bound columns is undefined.
+
+\wxheading{Remarks}
+
+This function can only be used if the datasource connection used by the
+wxDbTable instance was created with FwdOnlyCursors set to false. If the
+connection does not allow backward scrolling cursors, this function will
+return false, and the data contained in the bound columns will be undefined.
+
+\wxheading{See also}
+
+\helpref{wxDb::IsFwdOnlyCursors}{wxdbisfwdonlycursors},
+\helpref{wxDbTable::--}{wxdbtableminusminus}
+
+\membersection{wxDbTable::GetQueryTableName}\label{wxdbtablegetquerytablename}
+
+\func{const wxString \&}{GetQueryTableName}{}
+
+Accessor function that returns the name of the table/view that was indicated
+as being the table/view to query against when this wxDbTable instance was
+created.
+
+\wxheading{See also}
+
+\helpref{wxDbTable constructor}{wxdbtableconstr}
+
+\membersection{wxDbTable::GetRowNum}\label{wxdbtablegetrownum}
+
+\func{UWORD}{GetRowNum}{\void}
+
+Returns the ODBC row number for performing positioned updates and deletes.
+
+\wxheading{Remarks}
+
+This function is not being used within the ODBC class library and may be a
+candidate for removal if no use is found for it.
+
+Row number with some datasources/ODBC drivers is the position in the result set,
+while in others it may be a physical position in the database. Check your
+database documentation to find out which behavior is supported.
+
+\membersection{wxDbTable::GetTableName}\label{wxdbtablegettablename}
+
+\func{const wxString \&}{GetTableName}{}
+
+Accessor function that returns the name of the table that was indicated
+as being the table that this wxDbTable instance was associated with.
+
+\membersection{wxDbTable::GetTablePath}\label{wxdbtablegettablepath}
+
+\func{const wxString \&}{GetTablePath}{}
+
+Accessor function that returns the path to the data table that was indicated
+during creation of this wxDbTable instance.
+
+\wxheading{Remarks}
+
+Currently only applicable to dBase and MS-Access datasources.
+
+\membersection{wxDbTable::GetWhereClause}\label{wxdbtablegetwhereclause}
+
+\func{const wxString \&}{GetWhereClause}{}
+
+Accessor function that returns the current WHERE setting assigned with the
+\helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+
+\wxheading{See also}
+
+\helpref{wxDbTable::Where}{wxdbtablewhere}
+
+\membersection{wxDbTable::Insert}\label{wxdbtableinsert}
+
+\func{int }{Insert}{\void}
+
+Inserts a new record into the table being referenced by this wxDbTable
+instance. The values in the member variables of the wxDbTable instance are
+inserted into the columns of the new row in the database.
+
+\wxheading{Return value}
+
+\begin{verbatim}
+ DB_SUCCESS Record inserted successfully (value = 1)
+
+ DB_FAILURE Insert failed (value = 0)
+
+ DB_ERR_INTEGRITY_CONSTRAINT_VIOL
+ The insert failed due to an integrity
+ constraint violation (duplicate non-unique
+ index entry) is attempted.
+\end{verbatim}
+
+\wxheading{Remarks}
+
+A \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans} must be called after use of
+this function to commit or rollback the insertion.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Incomplete code snippet
+ wxStrcpy(parts->PartName, "10");
+ wxStrcpy(parts->PartDesc, "Part #10");
+ parts->Qty = 1000;
+ RETCODE retcode = parts->Insert();
+ switch(retcode)
+ {
+ case DB_SUCCESS:
+ parts->GetDb()->CommitTrans();
+ return(true);
+ case DB_ERR_INTEGRITY_CONSTRAINT_VIOL:
+ // Current data would result in a duplicate key
+ // on one or more indexes that do not allow duplicates
+ parts->GetDb()->RollbackTrans();
+ return(false);
+ default:
+ // Insert failed for some unexpected reason
+ parts->GetDb()->RollbackTrans();
+ return(false);
+ }
+\end{verbatim}
+
+\membersection{wxDbTable::IsColNull}\label{wxdbtableiscolnull}
+
+\func{bool }{IsColNull}{\param{UWORD }{colNumber}} const
+
+Used primarily in the ODBC class library to determine if a column value is
+set to "NULL". Works for all data types supported by the ODBC class library.
+
+\wxheading{Parameters}
+
+\docparam{colNumber}{The column number of the bound column as defined by the
+\helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs}
+calls which defined the columns accessible to this wxDbTable instance.}
+
+\wxheading{Remarks}
+
+NULL column support is currently not fully implemented as of wxWidgets 2.4.
+
+\membersection{wxDbTable::IsCursorClosedOnCommit}\label{wxdbtableiscursorclosedoncommit}
+
+\func{bool }{IsCursorClosedOnCommit}{\void}
+
+Accessor function to return information collected during the opening of the
+datasource connection that is used by this wxDbTable instance. The result
+returned by this function indicates whether an implicit closing of the cursor is
+done after a commit on the database connection.
+
+\wxheading{Return value}
+
+Returns true if the cursor associated with this wxDbTable object is closed
+after a commit or rollback operation. Returns false otherwise.
+
+\wxheading{Remarks}
+
+If more than one wxDbTable instance used the same database connection, all cursors
+which use the database connection are closed on the commit if this function
+indicates true.
+
+\membersection{wxDbTable::IsQueryOnly}\label{wxdbtableisqueryonly}
+
+\func{bool }{IsQueryOnly}{}
+
+Accessor function that returns a value indicating if this wxDbTable instance
+was created to allow only queries to be performed on the bound columns. If
+this function returns true, then no actions may be performed using this
+wxDbTable instance that would modify (insert/delete/update) the table's data.
+
+\membersection{wxDbTable::Open}\label{wxdbtableopen}
+
+\func{bool }{Open}{\param{bool }{checkPrivileges=false}, \param{bool }{checkTableExists=true}}
+
+Every wxDbTable instance must be opened before it can be used. This function
+checks for the existence of the requested table, binds columns, creates required
+cursors, (insert/select and update if connection is not wxDB\_QUERY\_ONLY) and
+constructs the insert statement that is to be used for inserting data as a new
+row in the datasource.
+
+NOTE: To retrieve data into an opened table, the of the table must be bound
+to the variables in the program via call(s) to
+\helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs} before calling Open().
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+\wxheading{Parameters}
+
+\docparam{checkPrivileges}{Indicates whether the Open() function should check
+whether the current connected user has at least SELECT privileges to access the
+table to which they are trying to open. Default is false.}
+
+\docparam{checkTableExists}{Indicates whether the Open() function should check
+whether the table exists in the database or not before opening it. Default is true.}
+
+\wxheading{Remarks}
+
+If the function returns a false value due to the table not existing, a log
+entry is recorded for the datasource connection indicating the problem
+that was detected when checking for table existence. Note that it is usually
+best for the calling routine to check for the existence of the table and for
+sufficient user privileges to access the table in the mode (wxDB\_QUERY\_ONLY or
+!wxDB\_QUERY\_ONLY) before trying to open the table for the best possible
+explanation as to why a table cannot be opened.
+
+Checking the user's privileges on a table can be quite time consuming during
+the open phase. With most applications, the programmer already knows that the
+user has sufficient privileges to access the table, so this check is normally
+not required.
+
+For best performance, open the table, and then use the
+\helpref{wxDb::TablePrivileges}{wxdbtableprivileges} function
+to check the users privileges. Passing a schema to the TablePrivileges()
+function can significantly speed up the privileges checks.
+
+\wxheading{See also}
+
+\helpref{wxDb::TableExists}{wxdbtableexists},
+\helpref{wxDb::TablePrivileges}{wxdbtableprivileges}
+\helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs}
+
+\membersection{wxDbTable::OrderBy}\label{wxdbtableorderby}
+
+\func{const wxString \&}{OrderBy}{}
+
+\func{void}{OrderBy}{\param{const wxString \&}{OrderBy}}
+
+Accessor function for the private class member wxDbTable::orderBy. Can be
+used as a synonym for
+\helpref{wxDbTable::GetOrderByClause}{wxdbtablegetorderbyclause}
+(the first form of this function) or
+\helpref{wxDbTable::SetOrderByClause}{wxdbtablesetorderbyclause}
+(the second form of this function).
+
+\wxheading{Parameters}
+
+\docparam{OrderBy}{A comma separated list of column names that indicate the
+alphabetized/numeric sorting sequence that the result set is to be returned
+in. If a FROM clause has also been specified, each column name specified in
+the ORDER BY clause should be prefaced with the table name to which the column
+belongs using DOT notation (TABLE\_NAME.COLUMN\_NAME).}
+
+\wxheading{Return value}
+
+The first form of this function returns the current value of the wxDbTable
+member variable ::orderBy.
+
+The second form of the function has no return value.
+
+\wxheading{See also}
+
+\helpref{wxDbTable::GetOrderByClause}{wxdbtablegetorderbyclause},
+\helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause}
+
+\membersection{wxDbTable::Query}\label{wxdbtablequery}
+
+\func{virtual bool }{Query}{\param{bool }{forUpdate=false}, \param{bool }{distinct=false}}
+
+\wxheading{Parameters}
+
+\docparam{forUpdate}{{\it OPTIONAL}. Gives you the option of locking records
+as they are retrieved. If the RDBMS is not capable of the FOR UPDATE clause,
+this argument is ignored. See
+\helpref{wxDbTable::CanSelectForUpdate}{wxdbtablecanselectforupdate} for
+additional information regarding this argument. Default is false.}
+\docparam{distinct}{{\it OPTIONAL}. Allows selection of only distinct values
+from the query (SELECT DISTINCT ... FROM ...). The notion of DISTINCT
+applies to all columns returned in the result set, not individual columns.
+Default is false.}
+
+\wxheading{Remarks}
+
+This function queries records from the datasource based on the three
+wxDbTable members: "where", "orderBy", and "from". Use
+\helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause} to filter on
+records to be retrieved (e.g. All users with a first name of "JOHN").
+Use \helpref{wxDbTable::SetOrderByClause}{wxdbtablesetorderbyclause} to
+change the sequence in which records are returned in the result set from
+the datasource (e.g. Ordered by LAST\_NAME). Use
+\helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} to allow inner
+joining of the base table (the one being associated with this instance of
+wxDbTable) with other tables which share a related field.
+
+After each of these clauses are set/cleared, call wxDbTable::Query() to
+fetch the result set from the datasource.
+
+This scheme has an advantage if you have to requery your record set
+frequently in that you only have to set your WHERE, ORDER BY, and FROM
+clauses once. Then to refresh the record set, simply call wxDbTable::Query()
+as frequently as needed.
+
+Note that repeated calls to wxDbTable::Query() may tax the database
+server and make your application sluggish if done too frequently or
+unnecessarily.
+
+The base table name is automatically prepended to the base column names in
+the event that the FROM clause has been set (is non-null) using
+\helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause}.
+
+The cursor for the result set is positioned {\it before} the first record in
+the result set after the query. To retrieve the first record, call either
+\helpref{wxDbTable::GetFirst}{wxdbtablegetfirst} (only if backward scrolling
+cursors are available) or
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext}. Typically, no data from the
+result set is returned to the client driver until a request such as
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext} is performed, so network
+traffic and database load are not overwhelmed transmitting data until the
+data is actually requested by the client. This behavior is solely dependent
+on the ODBC driver though, so refer to the ODBC driver's reference material
+for information on its behaviors.
+
+Values in the bound columns' memory variables are undefined after executing a
+call to this function and remain that way until a row in the result set is
+requested to be returned.
+
+The wxDbTable::Query() function is defined as "virtual" so that it may be
+overridden for application specific purposes.
+
+\normalbox{Be sure to set the wxDbTable's "where", "orderBy", and "from"
+member variables to "" if they are not to be used in the query. Otherwise,
+the results returned may have unexpected results (or no results) due to
+improper or incorrect query parameters constructed from the uninitialized
+clauses.}
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Incomplete code sample
+ parts->SetWhereClause("DESCRIPTION = 'FOOD'");
+ parts->SetOrderByClause("EXPIRATION_DATE");
+ parts->SetFromClause("");
+ // Query the records based on the where, orderBy and from clauses
+ // specified above
+ parts->Query();
+ // Display all records queried
+ while(parts->GetNext())
+ dispPart(parts); // user defined function
+\end{verbatim}
+
+\membersection{wxDbTable::QueryBySqlStmt}\label{wxdbtablequerybysqlstmt}
+
+\func{bool}{QueryBySqlStmt}{\param{const wxString \&}{pSqlStmt}}
+
+Performs a query against the datasource by accepting and passing verbatim the
+SQL SELECT statement passed to the function.
+
+\wxheading{Parameters}
+
+\docparam{pSqlStmt}{Pointer to the SQL SELECT statement to be executed.}
+
+\wxheading{Remarks}
+
+This is the most powerful form of the query functions available. This member
+function allows a programmer to write their own custom SQL SELECT statement
+for requesting data from the datasource. This gives the programmer access
+to the full power of SQL for performing operations such as scalar functions,
+aggregate functions, table joins, and sub-queries, as well as datasource
+specific function calls.
+
+The requirements of the SELECT statement are the following:
+
+\begin{enumerate}
+\item Must return the correct number of columns. In the derived
+wxDbTable constructor, it is specified how many columns are in
+the wxDbTable object. The SELECT statement must return exactly
+that many columns.
+\item The columns must be returned in the same sequence as specified
+when defining the bounds columns \helpref{wxDbTable::SetColDefs}{wxdbtablesetcoldefs},
+and the columns returned must be of the proper data type. For
+example, if column 3 is defined in the wxDbTable bound column
+definitions to be a float, the SELECT statement must return a
+float for column 3 (e.g. PRICE * 1.10 to increase the price by
+10%).
+\item The ROWID can be included in your SELECT statement as the {\bf last}
+column selected, if the datasource supports it. Use
+wxDbTable::CanUpdateByROWID() to determine if the ROWID can be
+selected from the datasource. If it can, much better
+performance can be achieved on updates and deletes by including
+the ROWID in the SELECT statement.
+\end{enumerate}
+
+Even though data can be selected from multiple tables (joins) in your select
+statement, only the base table associated with this wxDbTable object
+is automatically updated through the ODBC class library. Data from multiple
+tables can be selected for display purposes however. Include columns in
+the wxDbTable object and mark them as non-updateable (See
+\helpref{wxDbColDef}{wxdbcoldef} for details). This way columns can be
+selected and displayed from other tables, but only the base table will be
+updated automatically when performed through the
+\helpref{wxDbTable::Update}{wxdbtableupdate} function after using this type of
+query. To update tables other than the base table, use the
+\helpref{wxDbTable::Update}{wxdbtableupdate} function passing a SQL statement.
+
+After this function has been called, the cursor is positioned before the
+first record in the record set. To retrieve the first record, call
+either \helpref{wxDbTable::GetFirst}{wxdbtablegetfirst} or
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext}.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Incomplete code samples
+ wxString sqlStmt;
+ sqlStmt = "SELECT * FROM PARTS WHERE STORAGE_DEVICE = 'SD98' \
+ AND CONTAINER = 12";
+ // Query the records using the SQL SELECT statement above
+ parts->QueryBySqlStmt(sqlStmt);
+ // Display all records queried
+ while(parts->GetNext())
+ dispPart(&parts);
+
+ Example SQL statements
+ ----------------------
+
+ // Table Join returning 3 columns
+ SELECT PART_NUM, part_desc, sd_name
+ from parts, storage_devices
+ where parts.storage_device_id =
+ storage_devices.storage_device_id
+
+ // Aggregate function returning total number of
+ // parts in container 99
+ SELECT count(*) from PARTS where container = 99
+
+ // Order by clause; ROWID, scalar function
+ SELECT PART_NUM, substring(part_desc, 1, 10), qty_on_hand + 1, ROWID
+ from parts
+ where warehouse = 10
+ order by PART_NUM desc // descending order
+
+ // Subquery
+ SELECT * from parts
+ where container in (select container
+ from storage_devices
+ where device_id = 12)
+\end{verbatim}
+
+\membersection{wxDbTable::QueryMatching}\label{wxdbtablequerymatching}
+
+\func{virtual bool }{QueryMatching}{\param{bool }{forUpdate=false},
+\param{bool }{distinct=false}}
+
+QueryMatching allows querying of records from the table associated with
+the wxDbTable object by matching "columns" to values.
+
+For example: To query the datasource for the row with a PART\_NUMBER column
+value of "32", clear all column variables of the wxDbTable object, set the
+PartNumber variable that is bound to the PART\_NUMBER column in the wxDbTable
+object to "32", and then call wxDbTable::QueryMatching().
+
+\wxheading{Parameters}
+
+\docparam{forUpdate}{{\it OPTIONAL}. Gives you the option of locking records
+as they are queried (SELECT ... FOR UPDATE). If the RDBMS is not capable of
+the FOR UPDATE clause, this argument is ignored. See
+\helpref{wxDbTable::CanSelectForUpdate}{wxdbtablecanselectforupdate} for
+additional information regarding this argument. Default is false.}
+\docparam{distinct}{{\it OPTIONAL}. Allows selection of only distinct values
+from the query (SELECT DISTINCT ... FROM ...). The notion of DISTINCT
+applies to all columns returned in the result set, not individual columns.
+Default is false.}
+
+\wxheading{Remarks}
+
+The SQL WHERE clause is built by the ODBC class library based on all
+non-zero/non-NULL columns in your wxDbTable object. Matches can be on one,
+many or all of the wxDbTable's columns. The base table name is prepended
+to the column names in the event that the wxDbTable's FROM clause is non-null.
+
+This function cannot be used to perform queries which will check for
+columns that are 0 or NULL, as the automatically constructed WHERE clause
+only will contain comparisons on column member variables that are
+non-zero/non-NULL.
+
+The primary difference between this function and \helpref{wxDbTable::QueryOnKeyFields}{wxdbtablequeryonkeyfields}
+is that this function can query on any column(s) in the wxDbTable object.
+Note however that this may not always be very efficient. Searching on
+non-indexed columns will always require a full table scan.
+
+The cursor is positioned before the first record in the record set after
+the query is performed. To retrieve the first record, the program must call
+either \helpref{wxDbTable::GetFirst}{wxdbtablegetfirst} or
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext}.
+
+WHERE and FROM clauses specified using \helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+and \helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} are ignored by
+this function.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Incomplete code sample
+ parts->ClearMemberVars(); // Set all columns to zero
+ wxStrcpy(parts->PartNumber,"32"); // Set columns to query on
+ parts->OnHold = true;
+ parts->QueryMatching(); // Query
+ // Display all records queried
+ while(parts->GetNext())
+ dispPart(parts); // Some application defined function
+\end{verbatim}
+
+\membersection{wxDbTable::QueryOnKeyFields}\label{wxdbtablequeryonkeyfields}
+
+\func{bool }{QueryOnKeyFields}{\param{bool }{forUpdate=false},
+\param{bool }{distinct=false}}
+
+QueryOnKeyFields provides an easy mechanism to query records in the table
+associated with the wxDbTable object by the primary index column(s). Simply
+assign the primary index column(s) values and then call this member function
+to retrieve the record.
-\func{wxDBMS }{Dbms}{\void}
+Note that since primary indexes are always unique, this function implicitly
+always returns a single record from the database. The base table name is
+prepended to the column names in the event that the wxDbTable's FROM clause
+is non-null.
+
+\wxheading{Parameters}
+
+\docparam{forUpdate}{{\it OPTIONAL}. Gives you the option of locking records
+as they are queried (SELECT ... FOR UPDATE). If the RDBMS is not capable of
+the FOR UPDATE clause, this argument is ignored. See
+\helpref{wxDbTable::CanSelectForUpdate}{wxdbtablecanselectforupdate} for
+additional information regarding this argument. Default is false.}
+\docparam{distinct}{{\it OPTIONAL}. Allows selection of only distinct values
+from the query (SELECT DISTINCT ... FROM ...). The notion of DISTINCT
+applies to all columns returned in the result set, not individual columns.
+Default is false.}
\wxheading{Remarks}
-The return value will be of the enumerated type wxDBMS. This enumerated
-type contains a list of all the currently tested and supported databases.
+The cursor is positioned before the first record in the record set after
+the query is performed. To retrieve the first record, the program must call
+either \helpref{wxDbTable::GetFirst}{wxdbtablegetfirst} or
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext}.
-Additional databases may be work with these classes, but these databases
-returned by this function have been tested and confirmed to work with
-these ODBC classes.
+WHERE and FROM clauses specified using \helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+and \helpref{wxDbTable::SetFromClause}{wxdbtablesetfromclause} are ignored by
+this function.
+
+\wxheading{Example}
-enum wxDBMS includes:
\begin{verbatim}
- dbmsUNIDENTIFIED
- dbmsORACLE
- dbmsSYBASE_ASA
- dbmsSYBASE_ASE
- dbmsMY_SQL_SERVER
- dbmsMY_SQL
- dbmsPOSTGRES
- dbmsACCESS
- dbmsDBASE
- dbmsINFORMIX
+ // Incomplete code sample
+ wxStrcpy(parts->PartNumber, "32");
+ parts->QueryOnKeyFields();
+ // Display all records queried
+ while(parts->GetNext())
+ dispPart(parts); // Some application defined function
\end{verbatim}
-There are known issues with conformance to the ODBC standards with several
-datasources listed above. Please see the overview for specific details on
-on which datasource have which issues.
+\membersection{wxDbTable::Refresh}\label{wxdbtablerefresh}
-\wxheading{Return value}
+\func{bool}{Refresh}{\void}
-The return value will indicate which of the supported datasources is
-currently connected to by this connection. In the event that the
-datasource is not recognized, a value of 'dbmsUNIDENTIFIED' is returned.
+This function re-reads the bound columns into the memory variables, setting
+them to the current values stored on the disk.
-==========
-\membersection{wxDb::SetDebugErrorMessages}\label{wxdbsetdebugerrormessages}
+The cursor position and result set are unaffected by calls to this function.
+(The one exception is in the case where the record to be refreshed has been
+deleted by some other user or transaction since it was originally retrieved
+as part of the result set. For most datasources, the default behavior in
+this situation is to return the value that was originally queried for the
+result set, even though it has been deleted from the database. But this is
+datasource dependent, and should be tested before relying on this behavior.)
+
+\wxheading{Remarks}
-\func{void}{SetDebugErrorMessages}{\param{bool}{state}}
+This routine is only guaranteed to work if the table has a unique primary
+index defined for it. Otherwise, more than one record may be fetched and
+there is no guarantee that the correct record will be refreshed. The
+table's columns are refreshed to reflect the current data in the database.
-\docparam{state}{Either TRUE (debug messages are displayed) or FALSE (debug
-messages are not displayed.}
+\membersection{wxDbTable::SetColDefs}\label{wxdbtablesetcoldefs}
+
+\func{bool}{SetColDefs}{\param{UWORD }{index}, \param{const wxString \&}{fieldName},
+\param{int }{dataType}, \param{void *}{pData}, \param{SWORD }{cType},
+\param{int }{size}, \param{bool }{keyField = false}, \param{bool }{updateable = true},
+\param{bool }{insertAllowed = true}, \param{bool }{derivedColumn = false}}
+
+\func{wxDbColDataPtr *}{SetColDefs}{\param{wxDbColInf *}{colInfs}, \param{UWORD }{numCols}}
+
+\wxheading{Parameters}
+
+\docparam{index}{Column number (0 to n-1, where n is the number of columns
+specified as being defined for this wxDbTable instance when the
+wxDbTable constructor was called.}
+\docparam{fieldName}{Column name from the associated data table.}
+\docparam{dataType}{Logical data type. Valid logical types include:}
+
+\begin{verbatim}
+ DB_DATA_TYPE_VARCHAR : strings
+ DB_DATA_TYPE_INTEGER : non-floating point numbers
+ DB_DATA_TYPE_FLOAT : floating point numbers
+ DB_DATA_TYPE_DATE : dates
+ DB_DATA_TYPE_BLOB : binary large objects
+ DB_DATA_TYPE_MEMO : large strings
+\end{verbatim}
+
+\docparam{pData}{Pointer to the data object that will hold the column's
+value when a row of data is returned from the datasource.}
+\docparam{cType}{SQL C Type. This defines the data type that the SQL
+representation of the data is converted to to be stored in {\it pData}.
+Other valid types are available also, but these are the most common ones:}
+
+\begin{verbatim}
+ SQL_C_CHAR // string - deprecated: use SQL_C_WXCHAR
+ SQL_C_WXCHAR // string - Used transparently in unicode or non-unicode builds
+ SQL_C_LONG
+ SQL_C_ULONG
+ SQL_C_SHORT
+ SQL_C_USHORT
+ SQL_C_FLOAT
+ SQL_C_DOUBLE
+ SQL_C_NUMERIC
+ SQL_C_TIMESTAMP
+
+ SQL_C_BOOLEAN // defined in db.h
+ SQL_C_ENUM // defined in db.h
+\end{verbatim}
+
+\docparam{size}{Maximum size in bytes of the {\it pData} object.}
+\docparam{keyField}{{\it OPTIONAL}. Indicates if this column is part of the
+primary index. Default is false.}
+\docparam{updateable}{{\it OPTIONAL}. Are updates allowed on this column?
+Default is true.}
+\docparam{insertAllowed}{{\it OPTIONAL}. Inserts allowed on this column?
+Default is true.}
+\docparam{derivedColumn}{{\it OPTIONAL}. Is this a derived column (non-base
+table column for query only)? Default is false.}
+
+\docparam{colInfs}{Pointer to an array of wxDbColInf instances which contains
+all the information necessary to create {\it numCols} column definitions.}
+\docparam{numCols}{Number of elements of wxDbColInf type that are pointed
+to by {\it colInfs}, which are to have column definitions created from them.}
\wxheading{Remarks}
-Turns on/off debug error messages from the ODBC class library. When
-this function is passed TRUE, errors are reported to the user automatically
-in a text or pop-up dialog when an ODBC error occurs. When passed FALSE,
-errors are silently handled.
+If {\it pData} is to hold a string of characters, be sure to include enough
+space for the NULL terminator in pData and in the byte count of {\it size}.
-When compiled in release mode (FINAL=1), this setting has no affect.
+Using the first form of this function, if the column definition is not able
+to be created, a value of false is returned. If the specified index of the
+column exceeds the number of columns defined in the wxDbTable instance, an
+assert is thrown and logged (in debug builds) and a false is returned.
+
+A failure to create the column definition in the second form results in a
+value of NULL being returned.
+
+Both forms of this function provide a shortcut for defining the columns in
+your wxDbTable object. Use this function in any derived wxDbTable
+constructor when describing the column/columns in the wxDbTable object.
+
+The second form of this function is primarily used when the
+\helpref{wxDb::GetColumns}{wxdbgetcolumns} function was used to query the
+datasource for the column definitions, so that the column definitions are
+already stored in wxDbColInf form. One example use of using
+\helpref{wxDb::GetColumns}{wxdbgetcolumns} then using this function is if
+a data table existed in one datasource, and the table's column definitions
+were to be copied over to another datasource or table.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // Long way not using this function
+ wxStrcpy(colDefs[0].ColName, "PART_NUM");
+ colDefs[0].DbDataType = DB_DATA_TYPE_VARCHAR;
+ colDefs[0].PtrDataObj = PartNumber;
+ colDefs[0].SqlCtype = SQL_C_WXCHAR;
+ colDefs[0].SzDataObj = PART_NUMBER_LEN;
+ colDefs[0].KeyField = true;
+ colDefs[0].Updateable = false;
+ colDefs[0].InsertAllowed= true;
+ colDefs[0].DerivedCol = false;
+
+ // Shortcut using this function
+ SetColDefs(0, "PART_NUM", DB_DATA_TYPE_VARCHAR, PartNumber,
+ SQL_C_WXCHAR, PART_NUMBER_LEN, true, false, true, false);
+\end{verbatim}
+
+\membersection{wxDbTable::SetCursor}\label{wxdbtablesetcursor}
+
+\func{void}{SetCursor}{\param{HSTMT *}{hstmtActivate = (void **) wxDB\_DEFAULT\_CURSOR}}
+
+\wxheading{Parameters}
+
+\docparam{hstmtActivate}{{\it OPTIONAL}. Pointer to the cursor that is to
+become the current cursor. Passing no cursor handle will reset the cursor
+back to the wxDbTable's default (original) cursor that was created when the
+wxDbTable instance was first created. Default is wxDB\_DEFAULT\_CURSOR.}
+
+\wxheading{Remarks}
+
+When swapping between cursors, the member variables of the wxDbTable object
+are automatically refreshed with the column values of the row that the
+current cursor is positioned at (if any). If the cursor is not positioned,
+then the data in member variables is undefined.
+
+The only way to return back to the cursor that was in use before this
+function was called is to programmatically determine the current cursor's HSTMT
+{\bf BEFORE} calling this function using \helpref{wxDbTable::GetCursor}{wxdbtablegetcursor}
+and saving a pointer to that cursor.
\wxheading{See also}
-\helpref{wxDb constructor}{wxdbconstr}
+\helpref{wxDbTable::GetNewCursor}{wxdbtablegetnewcursor},
+\helpref{wxDbTable::GetCursor}{wxdbtablegetcursor},
+\helpref{wxDbTable::SetCursor}{wxdbtablesetcursor}
+\membersection{wxDbTable::SetFromClause}\label{wxdbtablesetfromclause}
+\func{void}{SetFromClause}{\param{const wxString \&}{From}}
-==========
-\membersection{wxDb::LogError}\label{wxdblogerror}
+Accessor function for setting the private class member wxDbTable::from
+that indicates what other tables should be inner joined with the wxDbTable's
+base table for access to the columns in those other tables.
-\func{void}{LogError}{\param{const char *}{errMsg} \param{const char *}{SQLState=0}}
+Synonym to this function is one form of \helpref{wxDbTable::From}{wxdbtablefrom}
+
+\wxheading{Parameters}
-\docparam{errMsg}{Free-form text to display describing the error to be logged.}
-\docparam{SQLState}{Native SQL state error}
+\docparam{From}{A comma separated list of table names that are to be inner
+joined with the base table's columns so that the joined table's columns
+may be returned in the result set or used as a portion of a comparison with
+the base table's columns. NOTE that the base tables name must NOT be included
+in the FROM clause, as it is automatically included by the wxDbTable class
+in constructing query statements.}
\wxheading{Remarks}
-Calling this function will enter a log message in the error list maintained
-for the database connection. This log message is free form and can be
-anything the programmer wants to enter in the error list.
-If SQL logging is turned on, the call to this function will also log the
-text into the SQL log file.
+Used by the \helpref{wxDbTable::Query}{wxdbtablequery} and
+\helpref{wxDbTable::Count}{wxdbtablecount} member functions to allow inner
+joining of records from multiple tables.
+
+Do {\bf not} include the keyword "FROM" when setting the FROM clause.
+
+If using the FROM clause when performing a query, be certain to include in
+the corresponding WHERE clause a comparison of a column from either the base
+table or one of the other joined tables to each other joined table to ensure
+the datasource knows on which column values the tables should be joined on.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ ...
+ // Base table is the "LOCATION" table, and it is being
+ // inner joined to the "PART" table via the field "PART_NUMBER"
+ // that can be related between the two tables.
+ location->SetWhereClause("LOCATION.PART_NUMBER = PART.PART_NUMBER")
+ location->SetFromClause("PART");
+ ...
+\end{verbatim}
\wxheading{See also}
-\helpref{wxDb::WriteSqlLog}{wxdbwritesqllog}
+\helpref{wxDbTable::From}{wxdbtablefrom},
+\helpref{wxDbTable::GetFromClause}{wxdbtablegetfromclause}
+
+\membersection{wxDbTable::SetColNull}\label{wxdbtablesetcolnull}
+
+\func{bool}{SetColNull}{\param{UWORD }{colNumber}, \param{bool }{set=true}}
+
+\func{bool}{SetColNull}{\param{const wxString \&}{colName},
+\param{bool }{set=true}}
+
+Both forms of this function allow a member variable representing a column
+in the table associated with this wxDbTable object to be set to NULL.
+
+The first form allows the column to be set by the index into the column
+definitions used to create the wxDbTable instance, while the second allows
+the actual column name to be specified.
+
+\wxheading{Parameters}
+
+\docparam{colNumber}{Index into the column definitions used when first defining
+this wxDbTable object.}
+\docparam{colName}{Actual data table column name that is to be set to NULL.}
+\docparam{set}{Whether the column is set to NULL or not. Passing true sets
+the column to NULL, passing false sets the column to be non-NULL. Default is
+true.}
+
+\wxheading{Remarks}
+
+No database updates are done by this function. It only operates on the
+member variables in memory. Use and insert or update function to store this
+value to disk.
+
+\membersection{wxDbTable::SetOrderByClause}\label{wxdbtablesetorderbyclause}
+
+\func{void}{SetOrderByClause}{\param{const wxString \&}{OrderBy}}
+
+Accessor function for setting the private class member wxDbTable::orderBy
+which determines sequence/ordering of the rows returned in the result set
+of a query.
+
+A synonym to this function is one form of the function \helpref{wxDbTable::OrderBy}{wxdbtableorderby}
+
+\wxheading{Parameters}
+
+\docparam{OrderBy}{A comma separated list of column names that indicate the
+alphabetized sorting sequence that the result set is to be returned in. If
+a FROM clause has also been specified, each column name specified in the
+ORDER BY clause should be prefaced with the table name to which the column
+belongs using DOT notation (TABLE\_NAME.COLUMN\_NAME).}
+
+\wxheading{Remarks}
+
+Do {\bf not} include the keywords "ORDER BY" when setting the ORDER BY clause.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ ...
+ parts->SetOrderByClause("PART_DESCRIP, QUANTITY");
+ ...
+
+ ...
+ location->SetOrderByClause("LOCATION.POSITION, PART.PART_NUMBER);
+ ...
+\end{verbatim}
+
+\wxheading{See also}
+
+\helpref{wxDbTable::OrderBy}{wxdbtableorderby},
+\helpref{wxDbTable::GetOrderByClause}{wxdbtablegetorderbyclause}
+
+\membersection{wxDbTable::SetQueryTimeout}\label{wxdbtablesetquerytimeout}
+
+\func{bool}{SetQueryTimeout}{\param{UDWORD }{nSeconds}}
+
+Allows a time period to be set as the timeout period for queries.
+
+\wxheading{Parameters}
+
+\docparam{nSeconds}{The number of seconds to wait for the query to complete
+before timing out.}
+
+\wxheading{Remarks}
+
+Neither Oracle or Access support this function as of yet. Other databases
+should be evaluated for support before depending on this function working
+correctly.
+
+\membersection{wxDbTable::SetWhereClause}\label{wxdbtablesetwhereclause}
+
+\func{void}{SetWhereClause}{\param{const wxString \&}{Where}}
+
+Accessor function for setting the private class member wxDbTable::where
+that determines which rows are returned in the result set by the datasource.
+
+A synonym to this function is one form of the function \helpref{wxDbTable::Where}{wxdbtablewhere}
+
+\wxheading{Parameters}
+
+\docparam{Where}{SQL "where" clause. This clause can contain any SQL language
+that is legal in standard where clauses. If a FROM clause has also been
+specified, each column name specified in the ORDER BY clause should be
+prefaced with the table name to which the column belongs using DOT notation
+(TABLE\_NAME.COLUMN\_NAME).}
+
+\wxheading{Remarks}
+
+Do {\bf not} include the keywords "WHERE" when setting the WHERE clause.
+
+\wxheading{Example}
+
+\begin{verbatim}
+ ...
+ // Simple where clause
+ parts->SetWhereClause("PART_NUMBER = '32'");
+ ...
+ // Any comparison operators
+ parts->SetWhereClause("PART_DESCRIP LIKE 'HAMMER%'");
+ ...
+ // Multiple comparisons, including a function call
+ parts->Where("QTY > 0 AND {fn UCASE(PART_DESCRIP)} LIKE '%DRILL%'");
+ ...
+ // Using parameters and multiple logical combinations
+ parts->Where("((QTY > 10) OR (ON_ORDER > 0)) AND ON_HOLD = 0");
+ ...
+ // This query uses an inner join (requiring a FROM clause also)
+ // that joins the PART and LOCATION table on he common field
+ // PART_NUMBER.
+ parts->Where("PART.ON_HOLD = 0 AND \
+ PART.PART_NUMBER = LOCATION.PART_NUMBER AND \
+ LOCATION.PART_NUMBER > 0");
+\end{verbatim}
+
+\wxheading{See also}
+
+\helpref{wxDbTable::Where}{wxdbtablewhere},
+\helpref{wxDbTable::GetWhereClause}{wxdbtablegetwhereclause}
+
+\membersection{wxDbTable::Update}\label{wxdbtableupdate}
+
+\func{bool }{Update}{\void}
+
+\func{bool }{Update}{\param{const wxString \&}{pSqlStmt}}
+
+The first form of this function will update the row that the current cursor
+is currently positioned at with the values in the memory variables that
+are bound to the columns. The actual SQL statement to perform the update
+is automatically created by the ODBC class, and then executed.
+
+The second form of the function allows full access through SQL statements for
+updating records in the database. Write any valid SQL UPDATE statement and
+submit it to this function for execution. Sophisticated updates can be
+performed using the full power of the SQL dialect. The full SQL statement
+must have the exact syntax required by the driver/datasource for performing
+the update. This usually is in the form of:
+
+\begin{verbatim}
+ UPDATE tablename SET col1=X, col2=Y, ... where ...
+\end{verbatim}
+
+\wxheading{Parameters}
+
+\docparam{pSqlStmt}{Pointer to SQL UPDATE statement to be executed.}
+
+\wxheading{Remarks}
+
+A \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans} must be called after use of
+this function to commit or rollback the update.
+\wxheading{Example}
+
+\begin{verbatim}
+ wxString sqlStmt;
+ sqlStmt = "update PART set QTY = 0 where PART_NUMBER = '32'";
+\end{verbatim}
+\membersection{wxDbTable::UpdateWhere}\label{wxdbtableupdatewhere}
-==========
-\membersection{wxDb::GetTypeInfXxxxx}\label{wxdbgettypeinf}
+\func{bool}{UpdateWhere}{\param{const wxString \&}{pWhereClause}}
-\func{wxDbSqlTypeInfo }{GetTypeInfDate}{\void}
-\func{wxDbSqlTypeInfo }{GetTypeInfFloat}{\void}
-\func{wxDbSqlTypeInfo }{GetTypeInfInteger}{\void}
-\func{wxDbSqlTypeInfo }{GetTypeInfVarchar}{\void}
+Performs updates to the base table of the wxDbTable object, updating only the
+rows which match the criteria specified in the {\it pWhereClause}.
+All columns that are bound to member variables for this wxDbTable instance
+that were defined with the "updateable" parameter set to true will be updated
+with the information currently held in the memory variable.
+
+\wxheading{Parameters}
+
+\docparam{pWhereClause}{Pointer to a valid SQL WHERE clause. Do not
+include the keyword 'WHERE'.}
\wxheading{Remarks}
+Care should be used when updating columns that are part of indexes with
+this function so as not to violate an unique key constraints.
+
+A \helpref{wxDb::CommitTrans}{wxdbcommittrans} or
+\helpref{wxDb::RollbackTrans}{wxdbrollbacktrans} must be called after use of
+this function to commit or rollback the update(s).
+
+\membersection{wxDbTable::Where}\label{wxdbtablewhere}
+
+\func{const wxString \&}{Where}{}
+
+\func{void}{Where}{\param{const wxString\& }{Where}}
+
+Accessor function for the private class member wxDbTable::where. Can be used
+as a synonym for \helpref{wxDbTable::GetWhereClause}{wxdbtablegetwhereclause}
+(the first form of this function) to return the current where clause or
+\helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause} (the second form
+of this function) to set the where clause for this table instance.
+
+\wxheading{Parameters}
+
+\docparam{Where}{A valid SQL WHERE clause. Do not include the keyword 'WHERE'.}
\wxheading{Return value}
+The first form of this function returns the current value of the wxDbTable
+member variable ::where.
+
+The second form of the function has no return value, as it will always set
+the where clause successfully.
+
+\wxheading{See also}
+
+\helpref{wxDbTable::GetWhereClause}{wxdbtablegetwhereclause},
+\helpref{wxDbTable::SetWhereClause}{wxdbtablesetwhereclause}
+
+\membersection{wxDbTable::operator $++$}\label{wxdbtableplusplus}
+
+\func{bool}{operator $++$}{\void}
+
+Synonym for \helpref{wxDbTable::GetNext}{wxdbtablegetnext}
+
+\wxheading{See also}
+
+\helpref{wxDbTable::GetNext}{wxdbtablegetnext}
+
+\membersection{wxDbTable::operator $--$}\label{wxdbtableminusminus}
+
+\func{bool}{operator $--$}{\void}
+
+Synonym for \helpref{wxDbTable::GetPrev}{wxdbtablegetprev}
+
+\wxheading{See also}
+
+\helpref{wxDbTable::GetPrev}{wxdbtablegetprev}
+
+\section{\class{wxDbTableInf}}\label{wxdbtableinf}
+
+\begin{verbatim}
+ tableName[0] = 0;
+ tableType[0] = 0;
+ tableRemarks[0] = 0;
+ numCols = 0;
+ pColInf = NULL;
+\end{verbatim}
+
+Currently only used by \helpref{wxDb::GetCatalog}{wxdbgetcatalog} internally
+and \helpref{wxDbInf}{wxdbinf} class, but may be used in future releases for
+user functions. Contains information describing the table (Name, type, etc).
+A pointer to a wxDbColInf array instance is included so a program can create a
+\helpref{wxDbColInf}{wxdbcolinf} array instance (using
+\helpref{wxDb::GetColumns}{wxdbgetcolumns})
+to maintain all information about the columns of a table in one memory
+structure.
+
+Eventually, accessor functions will be added for this class
+
+See the \helpref{database classes overview}{odbcoverview} for
+an introduction to using the ODBC classes.
+
+\wxheading{Include files}
+
+<wx/db.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDbTableInf::Initialize}\label{wxdbtableinfinitialize}
+
+Simply initializes all member variables to a cleared state. Called by
+the constructor automatically.
+
+\section{\class{wxDbGridColInfo}}\label{wxdbgridcolinfo}
+
+This class is used to define columns to be shown, names of the columns,
+order and type of data, when using \helpref{wxdbGridTableBase}{wxdbgridtablebase} to display
+a Table or query in a \helpref{wxGrid}{wxgrid}
+
+See the database grid example in \helpref{wxDbGridTableBase}{wxdbgridtablebase} for
+an introduction to using the wxDbGrid classes.
+
+\wxheading{Include files}
+
+<wx/dbgrid.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxDbGridColInfo::wxDbGridColInfo}\label{wxdbgridcolinfoctor}
+
+\func{}{wxDbGridColInfo}{\param{int }{colNumber}, \param{wxString }{type},
+ \param{wxString }{title}, \param{wxDbGridColInfo *}{next}}
+
+Default constructor. See the database grid example in \helpref{wxDbGridTableBase}{wxdbgridtablebase} to
+see two different ways for adding columns.
+
+
+\wxheading{Parameters}
+
+\docparam{colNumber}{Column number in the \helpref{wxDbTable}{wxdbtable} instance to be used (first column is 0).}
+\docparam{type}{Column type ,wxString specifying the grid name for the datatype in this column, or
+ use wxGRID\_VALUE\_DBAUTO to determine the type automatically from the \helpref{wxDbColDef}{wxdbcoldef} definition}
+\docparam{title}{The column label to be used in the grid display}
+\docparam{next}{A pointer to the next wxDbGridColInfo structure if using one-step
+construction, NULL terminates the list. Use Null also if using two step construction.}
+See the database grid example in \helpref{wxDbGridTableBase}{wxdbgridtablebase} to
+see two different ways for adding columns.
+
+\membersection{wxDbGridColInfo::\destruct{wxDbGridColInfo}}\label{wxdbgridcolinfodtor}
+
+\func{}{\destruct{wxDbGridColInfo}}{}
+
+Destructor.
+
+\membersection{wxDbGridColInfo::AddColInfo}\label{wxdbgridcolinfoaddcolinfo}
+
+\func{void}{AddColInfo}{\param{int }{colNumber},
+\param{wxString }{type}, \param{wxString }{title}}
+
+Use this member function for adding columns. See the database
+grid example in \helpref{wxDbGridTableBase}{wxdbgridtablebase} to
+see two different ways for adding columns.
+
+It is important to note that this class is merely a specifier to the \helpref{wxDbGridTableBase}{wxdbgridtablebase}
+constructor. Changes made to this datatype after the \helpref{wxDbGridTableBase}{wxdbgridtablebase} is called will
+not have any effect.
+
+\wxheading{Parameters}
+\docparam{colNumber}{Column number in the \helpref{wxDbTable}{wxdbtable} instance to be used (first column is 0).}
+\docparam{type}{Column type ,wxString specifying the grid name for the datatype in this column, or
+ use wxGRID\_VALUE\_DBAUTO to determine the type automatically from the \helpref{wxDbColDef}{wxdbcoldef} definition}
+\docparam{title}{The column label to be used in the grid display}
+
+\wxheading{Remarks}
+
+As wxDbTable must be defined with to have columns which match those to by a wxDbGridColInfo
+info structure as this is the structure which informs the grid of how you want to display your
+\helpref{wxDbTable}{wxdbtable}. If no datatype conversion or the referenced column number does not exist the
+the behavior is undefined.
+
+See the example at \helpref{wxDbGridColInfo::wxDbGridColInfo}{wxdbgridcolinfoctor}.
+
+\section{\class{wxDbGridTableBase}}\label{wxdbgridtablebase}
+
+You can view a database table in a grid using this class.
+
+If you are deriving your own wxDbTable subclass for your table , then you may consider
+overriding GetCol() and SetCol() to provide calculated fields. This does work but care should
+be taken when using wxDbGridTableBase in this way.
+
+The constructor and AssignDbTable() call allows you to specify the ownership if the wxDbTable
+object pointer. If you tell wxGridTableBase to take ownership , it will delete the passed wxDbTable
+when an new on is assigned or wxGridTableBase's destructor is called.
+However no checks for aliasing are done so Assign(table,..,true); Assign(table,..,true);
+is an error. If you need to requery an table object the preferred way is
+that the client keeps ownership.
+
+\wxheading{Derived From}
+
+\helpref{wxGridTableBase}{wxgridtablebase}
+
+\wxheading{Include files}
+
+<wx/dbgrid.h>
+
+
+\wxheading{Example}
+
+\begin{verbatim}
+ // First step, let's define wxDbTable
+ int numColumns = 2;
+ wxDbTable *table = new wxDbTable (db, tblName, numColumns);
+ int int_var;
+ wxChar string_name[255];
+ table->SetColDef (0, "column 0", DB_DATA_TYPE_INTEGER, &int_var,
+ SQL_C_LONG, sizeof(int_var), true);
+ table->SetColDef (1, "column 1", DB_DATA_TYPE_VARCHAR, &string_name,
+ SQL_C_LONG, sizeof(string_name), false);
+
+ // now let's define columns in the grid
+
+ // first way to do it
+ wxDbGridColInfo *columns;
+ columns = new wxDbGridColInfo(0, wxGRID_VALUE_LONG, "first column",
+ new wxDbGridColInfo(1, wxGRID_VALUE_STRING, "second column",
+ NULL);
+
+ // second way to do it
+ wxDbGridColInfo *columns;
+ // first column is special
+ columns = new wxDbGridColInfo(0, wxGRID_VALUE_LONG, "first column", NULL);
+ // all the rest
+ columns->AddColInfo (1, wxGRID_VALUE_STRING, "second column");
+
+ // second way may be better when columns are not known at compile time
+
+ // now, let's open the table and make a Query()
+ table->Open();
+ // this step is very important
+ table->SetRowMode (wxDbTable::WX_ROW_MODE_QUERY);
+ // in the grid we will see only the rows of the result query
+ m_dbTable->Query();
+
+ wxDbGridTableBase *dbgrid = new wxDbGridTableBase(table, columns, wxUSE_QUERY, true);
+ delete columns; // not needed anymore
+ wxGrid *grid = new wxGrid ( ... );
+ grid->SetTable(dbgrid, true);
+ grid->Fit();
+\end{verbatim}
+
+
+\wxheading{Include files}
+
+<wx/dbgrid.h>
+
+\wxheading{Helper classes and data structures}
+
+\membersection{wxDbGridTableBase::wxDbGridTableBase}\label{wxdbgridtablebaseconstr}
+
+\func{}{wxDbGridTableBase}{\param{wxDbTable *}{tab}, \param{wxDbGridColInfo *}{ColInfo},
+ \param{int }{count = wxUSE\_QUERY}, \param{bool }{takeOwnership = true}}
+
+Constructor.
+
+\wxheading{Parameters}
+
+\docparam{tab}{ The database table you want to display. Must be opened and queried before display the grid.
+See the example \helpref{above}{wxdbgridtablebase}.}
+\docparam{ColInfo}{ Columns titles, and other values. See \helpref{wxDbGridColInfo}{wxdbgridcolinfo}.}
+\docparam{count}{You can use a query result set (wxUSE\_QUERY, to use wxDbTable::Count(wxDbTable::Count()
+ or you can fix the total number of rows (count >= 0) to display, or specify it if you already know the size in avoid calling }
+
+\docparam{takeOwnership}{ If true, this class deletes wxDbTable when it stops
+referring to it, if false application must
+take care of deleting it. }
+
+\membersection{wxDbGridTableBase::ValidateRow}\label{wxdbgridtablebasevalidate}
+
+\func{void}{ValidateRow}{\param{int }{row}}
+
+It ensures that the row data is fetched from the database, and it the wxDbTable local buffer,
+the row number passed should be the grid row.
+
+\wxheading{Parameters}
+
+\docparam{row}{ Row where validation must be done. }
+
+\membersection{wxDbGridTableBase::UpdateRow}\label{wxdbgridtablebaseupdaterow}
+
+\func{bool}{UpdateRow}{\param{int }{row}}
+
+If row has changed it forces that row to be written back to the database, however support
+for detecting whether insert/update is required is currently not in wxDbTable, so this
+function is currently unsupported.
+
+\wxheading{Parameters}
+
+\docparam{row}{ Row you want to update. }
+
+\membersection{wxDbGridTableBase::AssignDbTable}\label{wxdbgridtablebaseassigndbtable}
+
+\func{bool}{AssignDbTable}{\param{wxDbTable *}{tab},\param{int }{count = wxUSE\_QUERY},
+\param{bool }{takeOwnership = true}}
+
+Resets the grid for using with a new database table, but using the same columns definition.
+This can be useful when re-querying the database and want to see the changes.
+
+\wxheading{Parameters}
+
+\docparam{tab}{ Database table you want to assign to the grid. }
+\docparam{count}{ Number of rows you want to show or wxUSE\_QUERY for using a query. }
+\docparam{takeOwnership}{ If false, user must take care of deleting tab after deleting
+the wxDbGridTableBase. If true, deletion is made by destructor class. }
+
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