<i>Time complexity O(1)</i><blockquote>Add the specified <i>member</i> to the set value stored at <i>key</i>. If <i>member</i>is already a member of the set no operation is performed. If <i>key</i>does not exist a new set with the specified <i>member</i> as sole member iscrated. If the key exists but does not hold a set value an error isreturned.</blockquote>
<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">
1 if the new element was added
-0 if the new element was already a member of the set
+0 if the element was already a member of the set
</pre><h2><a name="See also">See also</a></h2>
<ul><li> <a href="SremCommand.html">SREM</a></li><li> <a href="SismemberCommand.html">SISMEMBER</a></li><li> <a href="ScardCommand.html">SCARD</a></li><li> <a href="SmembersCommand.html">SMEMBERS</a></li><li> <a href="SinterCommand.html">SINTER</a></li><li> <a href="SinterstoreCommand.html">SINTERSTORE</a></li><li> <a href="SmoveCommand.html">SMOVE</a></li></ul>
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