ZRANK

ZRANK

返回有序集中指定成员的排名,按分数值递增(从小到大)顺序排列。

ZREVRANK就是从大到小排序，其他与ZRANK没区别，不再做记录

Command

$ redis-cli -h 127.0.0.1 -p 6379
127.0.0.1:6379> zadd salary 100 Tom 200 Lily 300 Paul 400 Jesse
(integer) 4
127.0.0.1:6379> zrank salary Tom
(integer) 0
127.0.0.1:6379> zrank salary Lily
(integer) 1
127.0.0.1:6379> zrank salary Paul
(integer) 2
127.0.0.1:6379> zrank salary Jesse
(integer) 3
127.0.0.1:6379> zrank salary fakeMember
(nil)
127.0.0.1:6379> EXISTS fakeSortedSetKey
(integer) 0
127.0.0.1:6379> zrank fakeSortedSetKey fakeMember
(nil)

Code

func zrank(c redis.Conn) {
    defer c.Do("DEL", "salary")
    c.Do("ZADD", "salary", 100, "Tom", 200, "Lily", 300, "Paul", 400, "Jesse")
    rank, _ := c.Do("ZRANK", "salary", "Tom")
    fmt.Println("Tom's rank is:", rank)
    rank, _ = c.Do("ZRANK", "salary", "Lily")
    fmt.Println("Lily's rank is:", rank)
    rank, _ = c.Do("ZRANK", "salary", "Paul")
    fmt.Println("Paul's rank is:", rank)
    rank, _ = c.Do("ZRANK", "salary", "Jesse")
    fmt.Println("Jesse's rank is:", rank)
    //  If specified member doesn't exist, returns nil.
    nilScore, _ := c.Do("ZRANK", "salary", "fakeMember")
    fmt.Println("If specified member doesn't exist, returns", nilScore)
    //  If key doesn't exist, returns nil.
    isExist, _ := c.Do("EXISTS", "fakeSortedSetKey")
    if isExist == 1 {
        c.Do("DEL", "fakeSortedSetKey")
    }
    nilScore, _ = c.Do("ZRANK", "fakeSortedSetKey", "fakeMember")
    fmt.Println("If key doesn't exist, returns", nilScore)
}

Output

$ go run main.go 
Tom's rank is: 0
Lily's rank is: 1
Paul's rank is: 2
Jesse's rank is: 3
If specified member doesn't exist, returns <nil>
If key doesn't exist, returns <nil>