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.
In Redis, the DEL command removes one or more keys. If a specified key doesn’t exist, it’s ignored.
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.
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.
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.
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.
In Redis, the MGET command allows us to get the values of multiple keys at once. The values are returned in an array reply.
If a specified key doesn’t exist, MGET returns nil for that key.
In Redis, the SET command sets a key to hold a given string value.
If the key already holds a value, it is overwritten with the new value. Also, any previous time to live associated with the key is discarded (assuming a successful SET operation).
In Redis, the GET command returns the value of a given key. If the key doesn’t exist, it returns nil.
An error is returned if the value stored at key is not a string.