Redis Sorted Sets: ZADD

ZADD key score1 member1 [score2 member2]

Redis ZADD command is used to add all the specified members with the specified scores to the sorted set stored at key. If a specified member is an existing member of the stored set, the score is updated and the element reinserted at the right position to ensure the correct ordering. A new sorted set with the specified members as sole members is created, when key dies not exists or the sorted set was empty. If the key exists but does not hold a sorted set, an error is returned.

Syntax:

ZADD KEY_NAME SCORE1 VALUE1.. SCOREN VALUEN

Available since

1.2.0.

Return Value

Integer replies The number of elements added to the sorted sets, not including elements already existing for which the score was updated.

Return Value Type

Integer

Example: Redis ZADD

127.0.0.1:6379> ZADD mycolorset 1 white
(integer) 1
127.0.0.1:6379> ZADD mycolorset 2 black
(integer) 1
127.0.0.1:6379> ZADD mycolorset 3 red
(integer) 1
127.0.0.1:6379> ZRANGE mycolorset 0 -1
1) "white"
2) "black"
3) "red"
127.0.0.1:6379> ZRANGE mycolorset 0 -1 WITHSCORES
1) "white"
2) "1"
3) "black"
4) "2"
5) "red"
6) "3"

Example: Redis ZADD : The score member can have multiple input

127.0.0.1:6379> ZADD mycolorset 4 blue 5 green
(integer) 2
127.0.0.1:6379> ZRANGE mycolorset 0 -1 WITHSCORES
 1) "white"
 2) "1"
 3) "black"
 4) "2"
 5) "red"
 6) "3"
 7) "blue"
 8) "4"
 9) "green"
10) "5"

Example: Redis ZADD : score is equal to the member being sort

127.0.0.1:6379> ZADD mycolorset 1 white 1 black 1 red 1 blue 1 green
(integer) 5
127.0.0.1:6379> ZRANGE mycolorset 0 -1 WITHSCORES
 1) "black"
 2) "1"
 3) "blue"
 4) "1"
 5) "green"
 6) "1"
 7) "red"
 8) "1"
 9) "white"
10) "1"

Example: Redis ZADD : duplicate member is not permitted

127.0.0.1:6379> ZADD mycolorset 1 orange
(integer) 1
127.0.0.1:6379> ZRANGE mycolorset 0 -1 WITHSCORES
 1) "black"
 2) "1"
 3) "blue"
 4) "1"
 5) "green"
 6) "1"
 7) "orange"
 8) "1"
 9) "red"
10) "1"
11) "white"
12) "1"

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