In Redis, we can use the SISMEMBER command to find out whether or not a set contains a given member.
Category: Redis
Fix “ERR wrong number of arguments for ‘sintercard’ command” in Redis
If you’re getting an error that reads “ERR wrong number of arguments for ‘sintercard’ command” in Redis, it’s because you’re calling the SINTERCARD command with the wrong number of arguments.
To fix this issue, make sure you’re passing the correct number of arguments.
Continue readingRedis SINTERCARD Command Explained
In Redis, the SINTERCARD command returns the cardinality of the set which would result from the intersection of all the given sets. It’s similar to SINTER, but instead of returning the result set, it returns just the cardinality of the result.
The SINTERCARD command was introduced in Redis 7.0.0.
Redis SINTERSTORE Command Explained
In Redis, the SINTERSTORE command is the same as the SINTER command, except that it stores the result in the specified key, instead of returning it.
It stores the members of the set resulting from the intersection of all the given sets.
If the destination key already exists, it’s overwritten. If it doesn’t exist, it’s created and the resulting members are added to it.
Continue readingRedis SINTER Command Explained
In Redis, the SINTER command returns the members of the set resulting from the intersection of all the given sets.
How to Set an Expiry Only When the New Expiry is Less Than the Existing Expiry in Redis
When setting a timeout on a key in Redis, we have the option of setting the timeout only if it’s less than the existing timeout. We can do this with the LT option of commands such as EXPIRE, EXPIREAT, PEXPIRE, and PEXPIREAT.
How to Return a Key’s Value and Set its Expiry in a Single Operation in Redis
In Redis, typically when we want to return a key’s value, we use the GET command. But there’s also a GETEX command (introduced in Redis 6.2.0) that allows us to get the value and return it’s expiry at the same time.
Redis SDIFFSTORE Command Explained
In Redis, the SDIFFSTORE command works just like the SDIFF command, except that instead of returning the result, it stores it in the key that we specify. The destination key will then hold the members of the set resulting from the difference between the first set and all the successive sets.
Redis SDIFF Command Explained
In Redis, the SDIFF command returns the members of the set resulting from the difference between the first set and all the successive sets. In other words, it returns all members of the first set that aren’t in any of the successive sets.
How to Return the Expiry Time as a Unix Timestamp in Redis
In Redis, we have several options for returning the expiry time of a key. One option from Redis 7.0.0 and above is to return it as a Unix timestamp.
When returning the expiry as a Unix timestamp, we can have it returned in seconds or milliseconds. To return it in seconds, we can use the EXPIRETIME command. To return it in milliseconds, we can use the PEXPIRETIME command.