2 <!DOCTYPE HTML PUBLIC 
"-//W3C//DTD HTML 4.01//EN"> 
   5         <link type=
"text/css" rel=
"stylesheet" href=
"style.css" /> 
  12             <img style=
"border:none" alt=
"Redis Documentation" src=
"redis.png"> 
  16             <div id=
"pagecontent"> 
  18 <!-- This is a (PRE) block.  Make sure it's left aligned or your toc title will be off. --> 
  19 <b>ZaddCommand: Contents
</b><br>  <a href=
"#ZADD _key_ _score_ _member_ (Redis >">ZADD _key_ _score_ _member_ (Redis 
></a><br>    <a href=
"#Return value">Return value
</a> 
  22                 <h1 class=
"wikiname">ZaddCommand
</h1> 
  29                     #sidebar 
<a href=
"SortedSetCommandsSidebar.html">SortedSetCommandsSidebar
</a><h1><a name=
"ZADD _key_ _score_ _member_ (Redis >">ZADD _key_ _score_ _member_ (Redis 
></a></h1> 1.1) =
 
  30 <i>Time complexity O(log(N)) with N being the number of elements in the sorted set
</i><blockquote>Add the specified 
<i>member
</i> having the specifeid 
<i>score
</i> to the sortedset stored at 
<i>key
</i>. If 
<i>member
</i> is already a member of the sorted setthe score is updated, and the element reinserted in the right position toensure sorting. If 
<i>key
</i> does not exist a new sorted set with the specified_member_ as sole member is crated. If the key exists but does not hold asorted set value an error is returned.
</blockquote> 
  31 <blockquote>The score value can be the string representation of a double precision floatingpoint number.
</blockquote> 
  32 <blockquote>For an introduction to sorted sets check the 
<a href=
"IntroductionToRedisDataTypes.html">Introduction to Redis data types
</a> page.
</blockquote> 
  33 <h2><a name=
"Return value">Return value
</a></h2><a href=
"ReplyTypes.html">Integer reply
</a>, specifically:
<br/><br/><pre class=
"codeblock python" name=
"code"> 
  34 1 if the new element was added
 
  35 0 if the element was already a member of the sorted set and the score was updated