doc/SortCommand.html

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  19 <b>SortCommand: Contents</b><br>&nbsp;&nbsp;<a href="#SORT _key_ BY _pattern_ LIMIT _start_ _end_ GET _pattern_ ASC|DESC ALPHA">SORT _key_ BY _pattern_ LIMIT _start_ _end_ GET _pattern_ ASC|DESC ALPHA</a><br>&nbsp;&nbsp;&nbsp;&nbsp;<a href="#Return value">Return value</a><br>&nbsp;&nbsp;&nbsp;&nbsp;<a href="#See Also">See Also</a>
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  22                 <h1 class="wikiname">SortCommand</h1>
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  29                     <h1><a name="SORT _key_ BY _pattern_ LIMIT _start_ _end_ GET _pattern_ ASC|DESC ALPHA">SORT _key_ BY _pattern_ LIMIT _start_ _end_ GET _pattern_ ASC|DESC ALPHA</a></h1>
  30 <blockquote>Sort the elements contained in the List or Set value at <i>key</i>. By defaultsorting is numeric with elements being compared as double precisionfloating point numbers. This is the simplest form of SORT.</blockquote>
  31 <pre class="codeblock python" name="code">
  32 SORT mylist
  33 </pre><blockquote>Assuming mylist contains a list of numbers, the return value will bethe list of numbers ordered from the smallest to the bigger number.In order to get the sorting in reverse order use DESC:</blockquote>
  34 <pre class="codeblock python python" name="code">
  35 SORT mylist DESC
  36 </pre><blockquote>ASC is also supported but it's the default so you don't really need it.If you want to sort lexicographically use ALPHA. Note that Redis isutf-8 aware assuming you set the right value for the LC_COLLATEenvironment variable.</blockquote>
  37 <blockquote>Sort is able to limit the number of results using the LIMIT option:</blockquote>
  38 <pre class="codeblock python python python" name="code">
  39 SORT mylist LIMIT 0 10
  40 </pre><blockquote>In the above example SORT will return only 10 elements, starting fromthe first one (star is zero-based). Almost all the sort options canbe mixed together. For example:</blockquote>
  41 <pre class="codeblock python python python python" name="code">
  42 SORT mylist LIMIT 0 10 ALPHA DESC
  43 </pre><blockquote>Will sort <i>mylist</i> lexicographically, in descending order, returning onlythe first 10 elements.</blockquote>
  44 <blockquote>Sometimes you want to sort elements using external keys as weights tocompare instead to compare the actual List or Set elements. For examplethe list <i>mylist</i> may contain the elements 1, 2, 3, 4, that are justthe unique IDs of objects stored at object_1, object_2, object_3and object_4, while the keys weight_1, weight_2, weight_3 and weight_4can contain weights we want to use to sort the list of objectsidentifiers. We can use the following command:</blockquote>
  45 <pre class="codeblock python python python python python" name="code">
  46 SORT mylist BY weight_*
  47 </pre><blockquote>the BY option takes a pattern (<code name="code" class="python">weight_*</code> in our example) that is usedin order to generate the key names of the weights used for sorting.Weight key names are obtained substituting the first occurrence of <code name="code" class="python">*</code>with the actual value of the elements on the list (1,2,3,4 in our example).</blockquote>
  48 <blockquote>Still our previous example will return just the sorted IDs. Often it isneeded to get the actual objects sorted (object_1, ..., object_4 in theexample). We can do it with the following command:</blockquote>
  49 <pre class="codeblock python python python python python python" name="code">
  50 SORT mylist BY weight_* GET object_*
  51 </pre><blockquote>Note that GET can be used multiple times in order to get more keys forevery element of the original List or Set sorted.</blockquote>
  52 <blockquote>Since Redis &gt;= 1.1 it's possible to also GET the list elements itselfusing the special # pattern:</blockquote>
  53 <pre class="codeblock python python python python python python python" name="code">
  54 SORT mylist BY weight_* GET object_* GET #
  55 </pre><h2><a name="Return value">Return value</a></h2><a href="ReplyTypes.html">Multi bulk reply</a>, specifically a list of sorted elements.<h2><a name="See Also">See Also</a></h2>
  56 <ul><li> <a href="SinterCommand.html">SINTER</a></li><li> <a href="SunionCommand.html">SUNION</a></li></ul>
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