Redis Set SISMEMBER Command

发表于2024-10-09|更新于2024-12-04|Redis Tutorial

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The Redis SISMEMBER command checks if a given element is a member of the set.

Syntax

The basic syntax of the SISMEMBER command is as follows:

1	SISMEMBER key member

It returns if member is a member of the set stored at key.

Available Since

Redis version >= 1.0.0

Time Complexity

O(1)

ACL Categories

@read, @set, @fast

Return Value

0 if the element is not a member of the set, or when the key does not exist.
1 if the element is a member of the set.

Example

127.0.0.1:6379> SADD key1 a b c d
(integer) 4
127.0.0.1:6379> SISMEMBER key1 a
(integer) 1
127.0.0.1:6379> SISMEMBER key1 e
(integer) 0

文章作者: Johnson Lin

文章链接: http://linjiangxiong.com/2024/10/09/redis-set-sismember-command/

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