How to set up expiration trigger events in Redis?
In Redis, you can trigger key expiration events by setting an expiration time for the key. When a key expires, Redis will perform some operations defined in the key expiration event.
To set up expiration trigger events, you can use the EXPIRE or PEXPIRE command to set the expiration time of a key, and use the EXPIREAT or PEXPIREAT command to set the expiration timestamp of a key.
Here are some examples of commands for setting up expired trigger events:
- Come to an end.
EXPIRE key_name seconds
- The expiration date has passed.
PEXPIRE key_name milliseconds
- EXPIREAT means the expiration date.
EXPIREAT key_name timestamp
- Expiration time specified as a Unix timestamp in milliseconds.
PEXPIREAT key_name timestamp
After setting an expiration time or expiration timestamp, Redis triggers a key expiration event and performs the corresponding actions when the key expires. The operations for key expiration events can be defined by configuring the Redis server, such as notifications or key deletion. To configure the operations for key expiration events, modify the notify-keyspace-events parameter in the Redis configuration file.
Please note that the expiration of keys in Redis is triggered in dictionary order. This means that if multiple keys expire at the same time, Redis will trigger the expiration events in dictionary order.