Sorted Sets

#redis #data-type

참고 자료

• Redis - 『Redis Sorted Sets Explained』 - on Youtube
• Commands?groupd=sorted_set - on redis.io

1. Sorted Sets

Sorted Sets

• Ordered collection of unique strings
• Floating point score
• manipulation by value, position, score or lexigraphically
• Set commands can be applied to Sorted Sets
  • Union
  • Intersiontion
• are not nested, hierarchies

• score 는 floating point 로 표현된다.
• 오름차순으로 정렬된다.
• score 가 같은 원소는 lexicographical 하게 정렬된다.

2. ZADD, ZRANGE

• ZADD
  • Adds one or more members to a sorted set
  • or update their scores
  • create the key if it does not exists

ZADD key [NX | XX] [GT | LT] [CH] [INCR] score member [score member
  ...]

• ZRANGE
  • returns members in a sorted set within a range of indexes
  • 범위를 나타낼때 ( 를 붙이면 exclusive 한 인덱스를 의미한다.
  • BYSCORE, BYLEX, REV 옵션들은 커맨드 자체로 대체될 수 있다.

ZRANGE key start stop [BYSCORE | BYLEX] [REV] [LIMIT offset count] [WITHSCORES]

redis> ZADD myzset 1 "one"
(integer) 1
redis> ZADD myzset 1 "uno"
(integer) 1
redis> ZADD myzset 2 "two" 3 "three"
(integer) 2
redis> ZRANGE myzset 0 -1 WITHSCORES
1) "one"
2) "1"
3) "uno"
4) "1"
5) "two"
6) "2"

3. ZSCORE, ZRANK

• zscore
  • 점수를 확인

redis> ZSCORE myzset "one"
(integer) 1

• zrank
  • 인덱스 (순위)를 확인

redis> ZSCORE myzset "one"
(integer) 0

4. set based 연산 - ZINTER, ZUNION, ZDIFF

ZINTER numkeys key [key ...] [WEIGHTS weight [weight ...]]
  [AGGREGATE <SUM | MIN | MAX>] [WITHSCORES]

ZUNION numkeys key [key ...] [WEIGHTS weight [weight ...]]
  [AGGREGATE <SUM | MIN | MAX>] [WITHSCORES]

ZDIFF numkeys key [key ...] [WITHSCORES]

score 에 대한 가중치를 조절하는 wight 와 aggragate 방식을 조절 할 수 있다.

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Last update: May 17, 2023
Created: May 16, 2023