<i>Time complexity: O(log(N))+O(M) with N being the number of elements in the sorted set and M the number of elements returned by the command, so if M is constant (for instance you always ask for the first ten elements with LIMIT) you can consider it O(log(N))</i><blockquote>Return the all the elements in the sorted set at key with a score between_min_ and <i>max</i> (including elements with score equal to min or max).</blockquote>
<blockquote>The elements having the same score are returned sorted lexicographically asASCII strings (this follows from a property of Redis sorted sets and does notinvolve further computation).</blockquote>
<blockquote>Using the optional LIMIT it's possible to get only a range of the matchingelements in an SQL-alike way. Note that if <i>offset</i> is large the commandsneeds to traverse the list for <i>offset</i> elements and this adds up to theO(M) figure.</blockquote>
<blockquote>The <b>ZCOUNT</b> command is similar to <b>ZRANGEBYSCORE</b> but instead of returningthe actual elements in the specified interval, it just returns the numberof matching elements.</blockquote><h2><aname="Exclusive intervals and infinity">Exclusive intervals and infinity</a></h2>
<i>min</i> and <i>max</i> can be -inf and +inf, so that you are not required to know what's the greatest or smallest element in order to take, for instance, elements "up to a given value".<br/><br/>Also while the interval is for default closed (inclusive) it's possible to specify open intervals prefixing the score with a "(" character, so for instance:
<preclass="codeblock python"name="code">
ZRANGEBYSCORE zset (1.3 5
</pre>
Will return all the values with score <b>> 1.3 and <= 5</b>, while for instance:
<preclass="codeblock python python"name="code">
ZRANGEBYSCORE zset (5 (10
</pre>
Will return all the values with score <b>> 5 and < 10</b> (5 and 10 excluded).
<h2><aname="Return value">Return value</a></h2>ZRANGEBYSCORE returns a <ahref="ReplyTypes.html">Multi bulk reply</a> specifically a list of elements in the specified score range.<br/><br/>ZCOUNT returns a <ahref="ReplyTypes.html">Integer reply</a> specifically the number of elements matching the specified score range.
