Redis: order collection Zset type data operation command

single key ： Multi order value

Orderly collection and consideration List aggregate （ Orderly , Order of insertion ） and Set aggregate （ disorder , Can't repeat ） Characteristics , But different from them

The elements of an ordered set are associated with a fraction ,redis It will automatically sort according to this score , By default, they are sorted from small to large

 

Ordered set type (Zset)

Redis Ordered set zset And collection set The same is true. string Collection of type elements , And duplicate members are not allowed .

The difference is zset Each element of the is associated with a score （ Scores can be repeated ）,redis Sort the members of the set from small to large by score .

 

 

1.zadd

grammar ：zadd key score member [score member…]

function ： Put one or more member Elements and score Values are added to the ordered set key in , If member In the collection , Then overwrite the original value ;score It can be an integer or floating point number .

Return value ： Numbers , Number of newly added elements .

  for example ：

 

 

2.zrange

grammar ：zrange key startIndex endIndex [WITHSCORES]

function ： Query ordered sets , The elements in the specified interval . Set members by score Sort values from small to large ;startIndex and endIndex from 0 Start with the first element ,1 For the second element , And so on ; startIndex and endIndex You can take negative numbers , Take from the back to the front ,-1 Represents the last but one element ;WITHSCORES Option to score and value Come back together .

Return value ： A set of members of a specified interval .

  for example ：

  Return with scores ：value and score

 

3.zrangebyscore

grammar ：zrangebyscore key min max [WITHSCORES ] [LIMIT offset count]

function ： Get ordered set key in , all score The value is between min and max Between （ Include min and max） Members of , Ordered members are incremented （ From small to large ） Sort ;

           Using symbols ”(“ Means to include min But does not include max;

           withscores Show score and value;

      limit Used to limit the number and interval of returned results , In the result set from offset Start , take count individual .

Return value ： Set data of specified interval

  for example ：

 

4.zrem

grammar ：zrem key member [member…]

function ： Delete ordered collection key One or more members of , Nonexistent members are ignored .

Return value ： Number of members successfully deleted , Excluding ignored members .

for example ：

 

5.zcard

grammar ：zcard key

effect ： Get ordered set key The number of element members of .

Return value ：key There is , Returns the number of collection elements ; key non-existent , return 0.

 

for example ：

 

6.zcount

grammar ：zcount key min max

function ： Return to ordered set  key  in , score  Values in  min  and  max  Between ( Include  score  The value is equal to  min  or  max ) The number of members of .

Return value ： Specifies the number of elements in an ordered set whose fraction is within a specified interval .

 

  for example ：

 

 

7.zrank

grammar ：zrank key member

function ： Get ordered set key Member of the member Ranking , Members of the ordered set press score The values are arranged in descending order , from 0 Start ranking ,score The smallest is 0 .

Return value ： Specifies the ranking of elements in an ordered set ; If the specified element does not exist , return nil.

for example ：

 

 

8.zscore

grammar ：zscore key member

function ： Get the ordered set key Medium element member The scores of .

Return value ： Returns the fraction of the elements of the specified ordered set .

for example ：

 

9.zrevrank

grammar ：zrevrank key member

function ： Get ordered set key Member of the member Ranking , Members of the ordered set press score The values are arranged in descending order , from 0 Start ranking ,score The biggest thing is 0 .

Return value ： Specifies the ranking of elements in an ordered set ; If the specified element does not exist , return nil.

  for example ：

10.zrevrange

grammar ：zrevrange key startIndex endIndex [WITHSCORES]

function ： Query ordered sets , The elements in the specified interval . Set members by score Sort values from large to small ;startIndex and endIndex from 0 Start with the first element ,1 For the second element , And so on ; startIndex and endIndex You can take negative numbers , Take from the back to the front ,-1 Represents the last but one element ;WITHSCORES Option to score and value Come back together .

Return value ： A set of members of a specified interval .

 

 

11.zrevrangebyscore

grammar ：zrevrangebyscore key max min  [WITHSCORES ] [LIMIT offset count]

function ： Get ordered set key in , all score The value is between max and min Between （ Include max and min） Members of , The order of members is decreasing （ From big to small ） Sort ;

           Using symbols ”(“ Means not to include min and max;

           withscores Show score and value;

      limit Used to limit the number and interval of returned results , In the result set from offset Start , take count individual .

Return value ： Set data of specified interval