SADD key member [member …]

Available since 1.0.0.

Time complexity: O(1) for each element added, so O(N) to add N elements when the command is called with multiple arguments.

Add the specified members to the set stored at key. Specified members that are already a member of this set are ignored. If key does not exist, a new set is created before adding the specified members.

An error is returned when the value stored at key is not a set.

*Return value

Integer reply: the number of elements that were added to the set, not including all the elements already present into the set.

*History

  • >= 2.4: Accepts multiple member arguments. Redis versions before 2.4 are only able to add a single member per call.

*Examples

redis> SADD myset "Hello" 

  1. (integer) 1

redis> SADD myset "World" 

  1. (integer) 1

redis> SADD myset "World" 

  1. (integer) 0

redis> SMEMBERS myset 

  1. 1) "Hello"
  2. 2) "World"
redis>