Fix: “ERR syntax error” when using SPOP in Redis

If you’re getting an error that reads “ERR syntax error” in Redis, it could be because you’re calling the SPOP command with too many arguments.

At the time of writing, I find that I only get this argument when I pass too many arguments. If I pass no arguments, I get a different error.

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How to Get a Substring in Redis

If we have a key that holds a string value, we can use the GETRANGE command to get a substring from that value.

Redis also has a SUBSTR command that does the same thing, but that was deprecated in Redis 2.0.0, in favour of the GETRANGE command.

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Fix: “ERR wrong number of arguments for ‘spop’ command” in Redis

If you’re getting an error that reads “ERR wrong number of arguments for ‘spop’ command” in Redis, it’s because you’re calling the SPOP command with the wrong number of arguments.

At the time of writing, I find that I only get this argument when I pass no arguments. If I pass too many, I get a different error.

In any case, to fix this issue, be sure to pass at least one argument to the command (and at the time of writing, no more than two).

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2 Ways to Return a Random Member from a Redis Set

Redis provides us with two commands that allow us to get one or more random members from a given set – SRANDMEMBER and SPOP.

Actually, the commands are slightly different in that one deletes the random member whereas the other doesn’t, and so the command you choose will depend on whether or not you want to delete the random member at the same time.

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Fix: “ERR wrong number of arguments for ‘sismember’ command” in Redis

If you’re getting an error that reads “ERR wrong number of arguments for ‘sismember’ command” in Redis, it’s because you’re calling the SISMEMBER command with the wrong number of arguments.

To fix this issue, make sure you’re passing the correct number of arguments. At the time of writing, the correct number of arguments for this command is two.

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