In Redis, the SMEMBERS command returns all members of a given set. We specify the key name of the set when we call the command.

Syntax

The syntax goes like this:

SMEMBERS key

So all we do is pass the name of the key that contains the set.

Example

Suppose we create the following set:

SADD animals Cat Dog Mouse Zebra

We can use the SMEMBERS command to return all values:

SMEMBERS animals

Result:

1) "Cat"
2) "Dog"
3) "Mouse"
4) "Zebra"

As expected, all elements in the set are returned in an array.

Non-Existent Key

Here’s what happens when I pass a key that doesn’t exist:

SMEMBERS oops

Result:

(empty array)

We get an empty array.

Passing the Wrong Number of Arguments

Passing the wrong number of arguments results in an error:

SMEMBERS animals Dog

Result:

(error) ERR wrong number of arguments for 'smembers' command

The error tells us what we did wrong.

We get the same error if we call the command without any arguments:

SMEMBERS

Result:

(error) ERR wrong number of arguments for 'smembers' command