Redis STRLEN 命令
语法
1 | STRLEN key |
可用版本
≥ 2.2.0
时间复杂度
$O(1)$
ACL类别
@read, @string, @fast
返回存储在 key 处的字符串值的长度。当 key 存储的值不是字符串类型时，则返回错误。
返回值
返回一个整数：
- key 对应值的字符串长度；
- 如果 key 不存在，则返回 0。
示例 1
返回键 user 存储的字符串的长度：
1 | redis> SET user "JOHNSON LIN" |
示例 2
键 nonexisting 不存在，STRLEN 操作返回 0：
1 | redis> EXISTS nonexisting |
示例 3
键 listkey 存储的值不是字符串类型，STRLEN 操作返回错误：
1 | redis> RPUSH listkey "JOHNSON LIN" |
（END）
All articles on this blog are licensed under CC BY-NC-SA 4.0 unless otherwise stated.
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