## sDiff ##### *Description* Performs the difference between N sets and returns it. 执行差集操作在N个不同的SET容器之间，并返回结果。这个操作取得结果是第一个SET相对于其他参与计算的SET集合的差集。(Result = SET0 - (SET1 UNION SET2 UNION ....SET N)) ##### *Parameters* *Keys*: key1, key2, ... , keyN: Any number of keys corresponding to sets in redis. ##### *Return value* *Array of strings*: The difference of the first set will all the others. 返回数组,返回的是第一个SET集合相对于其他集合的差集(first set - (N sets)) 返回数组：第一个SET集合的补 ##### *Example* ``` <pre class="calibre9">$redis->delete('s0', 's1', 's2'); $redis->sAdd('s0', '1'); $redis->sAdd('s0', '2'); $redis->sAdd('s0', '3'); $redis->sAdd('s0', '4'); $redis->sAdd('s1', '1'); $redis->sAdd('s2', '3'); var_dump($redis->sDiff('s0', 's1', 's2')); ``` Return value: all elements of s0 that are neither in s1 nor in s2. ``` <pre class="calibre9">array(2) { [0]=> string(1) "4" [1]=> string(1) "2" } ``` ##