In Redis, the STRLEN command returns the length of the string stored at a given key.
Tag: string
Redis PSETEX Command Explained
The Redis PSETEX command sets a key to hold a given string value, and sets that key to time out after a given number of milliseconds.
Redis SETEX Command Explained
In Redis, the SETEX command sets a key to hold a given string value, and sets that key to time out after a given number of seconds.
Redis APPEND Command Explained
In Redis, the APPEND command appends a given value to the end of the value of a specified key.
If the key doesn’t exist, APPEND creates the key with the empty string and appends the value to it (so it basically works like the SET command in this case).
Redis GETDEL Command Explained
The Redis GETDEL command gets the value of a given key, then deletes that key. It’s similar to the GET command, except that it deletes the key on success (the GET command doesn’t delete the key – it only returns its value).
An error is returned if the value stored at key is not a string.
The GETDEL command was introduced in Redis 6.2.0.
Redis DEL Command Explained
In Redis, the DEL command removes one or more keys. If a specified key doesn’t exist, it’s ignored.
Redis LCS Command Explained
In Redis, the LCS command implements the longest common subsequence algorithm.
The longest common subsequence algorithm finds the longest subsequence common to all sequences in a set of sequences. Note that this is different to the longest common string algorithm (also known as the longest common substring algorithm), which requires that matching characters in the string are contiguous. The longest common subsequence algorithm, on the other hand, doesn’t require matching characters to be contiguous.
The LCS command was introduced in Redis 7.0.0.
Continue readingRedis GETEX Command Explained
The Redis GETEX command enables us to get the value of a key, then set the key’s expiration. We can also use it to remove any existing expiration associated with the key.
Redis SETNX Command Explained
The Redis SETNX command sets a key to a given value, but only if the key doesn’t already exist. If the key already holds a value, no operation is performed.
Note: The SET command can do the same thing, and it’s possible that the SETNX command may be deprecated at some point. Therefore, it’s probably a good idea to use SET instead of SETNX if possible.
Redis MSETNX Command Explained
In Redis, the MSETNX command allows us to set multiple keys at once, but only if none of them exist.
This allows us to set multiple keys representing different fields of a single logical object in a way that ensures that either all the fields are set, or none are set.
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