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.

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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.

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