How to set the key in redis
The Redis SET command is used to set the value of a given key. If the key already stores another value, SET overwrites the old value regardless of the type.
The basic syntax of the redis SET command is as follows:
redis 127.0.0.1:6379> SET KEY_NAME VALUE
Return value:
In versions prior to Redis 2.6.12, the SET command always returns OK.
Starting from Redis version 2.6.12, SET will only return OK when the setting operation is successfully completed
Example:
Create a key in redis and set the value .
# 对不存在的键进行设置 redis 127.0.0.1:6379> SET key "value" OK redis 127.0.0.1:6379> GET key "value" # 对已存在的键进行设置 redis 127.0.0.1:6379> SET key "new-value" OK redis 127.0.0.1:6379> GET key "new-value"
The Redis key command is used to manage redis keys.
The basic syntax of the Redis key command is as follows:
redis 127.0.0.1:6379> COMMAND KEY_NAME
Example:
redis 127.0.0.1:6379> SET runoobkey redis OK redis 127.0.0.1:6379> DEL runoobkey(integer) 1
In the above example, DEL is a command and runoobkey is a key. If the key is successfully deleted, (integer) 1 will be output after the command is executed, otherwise (integer) 0 will be output.
Basic commands related to Redis keys:
1, DEL key
This command Used to delete the key when it exists.
2, DUMP key
Serialize the given key and return the serialized value.
3. EXISTS key
Check whether the given key exists.
4. EXPIRE key seconds
Set the expiration time for the given key, in seconds.
5. EXPIREAT key timestamp
EXPIREAT has a similar function to EXPIRE, and is used to set the expiration time for the key. The difference is that the time parameter accepted by the EXPIREAT command is UNIX timestamp (unix timestamp).
6 、PEXPIRE key milliseconds
Set the expiration time of key in milliseconds.
7. PEXPIREAT key milliseconds-timestamp
Set the timestamp of the key expiration time (unix timestamp) in milliseconds
8. KEYS pattern
Find all items that match the given pattern ( pattern) key.
9. MOVE key db
Move the key of the current database to the given database db.
10. PERSIST key
Remove the expiration time of the key, and the key will be maintained permanently.
11. PTTL key
Returns the remaining expiration time of the key in milliseconds.
12. TTL key
Returns the remaining survival time (TTL, time to live) of the given key in seconds.
13. RANDOMKEY
Randomly returns a key from the current database.
14. RENAME key newkey
Modify the name of the key
15. RENAMENX key newkey
Only when newkey does not exist, rename the key to newkey.
16. TYPE key
Returns the type of value stored in key.
For more Redis related knowledge, please visit the Redis usage tutorial column!
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