In Redis, the KEYS
command returns all keys in the database matching a given pattern.
Tag: commands
Redis DUMP Command Explained
The Redis DUMP
command serialises the value stored at a specified key in a Redis-specific format and returns it to the user.
The serialisation format contains a 64-bit checksum that is used to make sure errors will be detected. The values are in the same format used by the RDB. Also, an RDB version is encoded inside the serialised value, so that different Redis versions with incompatible RDB formats will refuse to process the serialised value.
Continue readingRedis TOUCH Command Explained
The Redis TOUCH
command alters the last access time of a key or keys. It allows us to alter the access time of a key without accessing it directly.
Redis EXISTS Command Explained
In Redis, the EXISTS
command checks whether the specified keys exist. It returns an integer reply with the number of keys that exist.
We can use the command to check for the existence of one key or multiple keys.
Continue readingRedis SORT_RO Command Explained
The Redis SORT_RO
command is a read-only variant of the SORT
command. It allows us to sort lists, sets, and sorted sets.
The SORT
command enables us to have the sorted elements returned to the client, or stored in a separate key. But the SORT_RO
command only allows us to have them returned to the client.
The SORT_RO
variant was introduced in Redis 7.0.0 to enable SORT
functionality in read-only replicas without breaking compatibility on command flags.
Redis SORT Command Explained
In Redis, the SORT
command allows us to sort lists, sets, and sorted sets.
We can have the sorted elements returned to the client, or we can store them in a separate key.
Continue readingRedis TYPE Command Explained
In Redis, the TYPE
command returns a key’s type. More specifically, it returns the string representation of the type of the value stored at a given key.
Redis UNLINK Command Explained
In Redis, the UNLINK
command removes the specified keys. It’s similar to the DEL
command, except that it performs the memory reclaiming in a different thread, so it is not blocking. The DEL
command, on the other hand, doesn’t do this.
More specifically, the UNLINK
command unlinks the keys from the keyspace, and then removes it later asynchronously.
Redis RENAMENX Command Explained
In Redis, the RENAMENX
command renames a key, but only if the new key doesn’t already exist.
RENAMENX
is similar to the RENAME
command, except that it only renames the key if the new one doesn’t already exist. The RENAME
command on the other hand, will overwrite the new key if it already exists.
How to Run the Same Command Multiple Times in Redis
The Redis CLI allows us to easily run a command multiple times. All we need to do is prefix the command with the number of times we want it to run.
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