Spring 5.0 By Example

Main commands

The following are the main commands listed with their usages:

• SADD: It adds the element in a requested key. Also, the return of this command is the number of the element added to the set:

        SADD "unique-visitors" "joe"        SADD "unique-visitors" "mary"

As we can see, the command returned one because we added one user each time.

• SMEMBERS: It returns all the members of a requested key:

       SMEMBERS "unique-visitors"

The command will return joe and mary because those are the values stored in the unique-visitors key.

• SCARD: It returns the numbers of elements of a requested key:

        SCARD "unique-visitors"

The command will return the number of elements stored in the requested keys, in this case, the output will be 2.