Redis MSETNX 命令
语法
1 | MSETNX key value [key value ...] |
可用版本
≥ 1.0.1
时间复杂度
$O(N)$
其中 N 是要设置的 key 的数量。
ACL类别
@write, @string, @slow
将给定的键设置为其各自的值。但只要有一个键已经存在，MSETNX 就不会执行任何操作。
由于这种语义，可以使用 MSETNX 来设置代表唯一逻辑对象的不同字段的不同键，以确保设置所有字段或根本不设置任何字段。
MSETNX 是原子的，所以所有给定的键都是一次性设置的。也就是说，客户端不可能看到一些键被更新，而另一些键却没有变化。
返回值
返回一个整数，具体而言：
- 1 - 如果所有的键都被设置了，则返回 1；
- 0 - 如果没有设置任何键（至少有一个键已经存在），则返回 0。
示例
1 | redis> MSETNX key1 "Hello" key2 "there" |
（END）
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