<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>
<blockquote>The score value can be the string representation of a double precision floatingpoint number.</blockquote>
<blockquote>For an introduction to sorted sets check the <ahref="IntroductionToRedisDataTypes.html">Introduction to Redis data types</a> page.</blockquote>