What is the function of the setnx command in Redis?

setnx命令是Redis中的一个原子性操作命令，用于设置一个键值对，但只有在该键不存在时才会设置成功。如果键已经存在，则不进行任何操作。

The purpose of the SETNX command is to implement a distributed lock. When multiple clients attempt to acquire the lock for the same resource simultaneously, only one client will successfully acquire the lock while the others will wait or execute other logic.

The setnx command ensures that only one client can obtain the lock in high concurrency situations, preventing deadlocks and data inconsistencies.

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SETNX lockkey "value"

If the lockkey does not exist, executing the above command will set the value of lockkey to “value” and return 1; if lockkey already exists, no operation will be performed and 0 will be returned.