Redis Sorted Sets: ZINCRBY

ZINCRBY key increment member

Redis ZINCRBY command is used to increment the score or member in the sorted set stored at key by an incremental value. If no member exists in the sorted set, it is added with incremental value as specified. If the  key does not exist, a new sorted set with the specified member as its sole member is created. When key exists but does not hold a sorted set an error will return.

Syntax:

ZINCRBY KEY INCREMENT MEMBER

Available since

1.2.0.

Return Value

String reply, the new score of the member (a double precision floating point number), represented as a string.

Return Value Type

String

Example: Redis ZINCRBY: score increase, decrease

127.0.0.1:6379> ZADD myvisit 1200 facebook.com 1800 google.com 1500 stackoverflow.com
(integer) 3
127.0.0.1:6379> ZREVRANGE myvisit 0 -1 WITHSCORES
1) "google.com"
2) "1800"
3) "stackoverflow.com"
4) "1500"
5) "facebook.com"
6) "1200"

The facebook.com increased by 500

127.0.0.1:6379> ZINCRBY myvisit 500 facebook.com
"1700"
127.0.0.1:6379> ZREVRANGE myvisit 0 -1 WITHSCORES
1) "google.com"
2) "1800"
3) "facebook.com"
4) "1700"
5) "stackoverflow.com"
6) "1500"

The google.com decreased by 200

127.0.0.1:6379> ZINCRBY myvisit -200 google.com
"1600"

The rank has changed

127.0.0.1:6379> ZREVRANGE myvisit 0 -1 WITHSCORES
1) "facebook.com"
2) "1700"
3) "google.com"
4) "1600"
5) "stackoverflow.com"
6) "1500"

Example: Redis ZINCRBY: using decimal

127.0.0.1:6379> ZADD myliteracy 8.3 Canada 6.7 Brazil 5.1 India 4.2 Koria 7.9 Japan
(integer) 5
127.0.0.1:6379> ZREVRANGE myliteracy 0 -1 WITHSCORES
 1) "Canada"
 2) "8.3000000000000007"
 3) "Japan"
 4) "7.9000000000000004"
 5) "Brazil"
 6) "6.7000000000000002"
 7) "India"
 8) "5.0999999999999996"
 9) "Koria"
10) "4.2000000000000002"
127.0.0.1:6379> ZINCRBY myliteracy 1.7 India
"6.7999999999999998"

Example: Redis ZINCRBY: generate key member

If you do not have to create and save an existing key or member. At this time, the criteria score is 0.0.

127.0.0.1:6379> ZINCRBY dailyviewers 1 450205
"1"
127.0.0.1:6379> ZINCRBY dailyviewers 1 450205
"2"
127.0.0.1:6379> ZINCRBY dailyviewers 1 450205
"3"
127.0.0.1:6379> ZINCRBY dailyviewers 1 450306
"1"
127.0.0.1:6379> ZINCRBY dailyviewers 1 450306
"2"
127.0.0.1:6379> ZREVRANGE dailyviewers 0 -1 WITHSCORES
1) "450205"
2) "3"
3) "450306"
4) "2"

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