Redis命令-集合-sinter

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原文

http://redis.io/commands/sinter

 

简介

Intersect multiple sets.

 

多个集合的交集。

 

语法

SINTER key [key ...]

 

版本

Available since 1.0.0.

 

自1.0.0版本可用。

 

时间复杂度

Time complexity: O(N*M) worst case where N is the cardinality of the smallest set and M is the number of sets.

 

O(N*M)：N是最小集合的基数，M是集合的数量。

 

描述

Returns the members of the set resulting from the intersection of all the given sets.

 

返回所有给定集合的交集的元素。

 

For example:
key1 = {a,b,c,d}
key2 = {c}
key3 = {a,c,e}
SINTER key1 key2 key3 = {c}

 

Keys that do not exist are considered to be empty sets. With one of the keys being an empty set, the resulting set is also empty (since set intersection with an empty set always results in an empty set).

 

如果key不存在被看作是空集合。如果有一个key是空集合，则返回的结果集合也是空的。

 

返回值

Array reply: list with members of the resulting set.

 

Array：结果集合的成员列表。

 

例子

redis>  SADD key1 "a"
(integer) 1
redis>  SADD key1 "b"
(integer) 1
redis>  SADD key1 "c"
(integer) 1
redis>  SADD key2 "c"
(integer) 1
redis>  SADD key2 "d"
(integer) 1
redis>  SADD key2 "e"
(integer) 1
redis>  SINTER key1 key2
1) "c"
redis>