redis之set 集合命令详解

末蓝、 2022-06-16 06:18 269阅读 0赞

*  集合 set 相关命令
    
     *  sadd key value1 value2
        
         *   *  作用 往集合key中增加元素
             *  srem value1 value2
             *  spop key
             *  srandmember key
             *  sismember key value
             *  smembers key
             *  scard key
             *  smove source dest value
             *  sinter key1 key2 key3
             *  sinterstore dest key1 key2 key3
             *  sunion key1 key2 Keyn
             *  sdiff key1 key2 key3

# 集合 set 相关命令 #

> 集合的性质: 唯一性,无序性,确定性  
> 注: 在string和link的命令中,可以通过range 来访问string中的某几个字符或某几个元素  
> 但,因为集合的无序性,无法通过下标或范围来访问部分元素.  
> 因此想看元素,要么随机先一个,要么全选

## sadd key value1 value2 ##

#### 作用: 往集合key中增加元素 ####

<?php
    $redis->sAdd('k', 'v1');// int(1)
    $redis->sAdd('k', 'v1', 'v2', 'v3');// int(2)

#### srem value1 value2 ####

作用: 删除集合中集为 value1 value2的元素  
返回值: 忽略不存在的元素后,真正删除掉的元素的个数

<?php
    var_dump( $redis->sAdd('k', 'v1', 'v2', 'v3') );// int(3)
    var_dump( $redis->sRem('k', 'v2', 'v3') );// int(2)
    var_dump( $redis->sMembers('k') ); // array(1) {[0]=> string(2) "v1"}

#### spop key ####

作用: 返回并删除集合中key中1个随机元素

随机–体现了无序性

<?php
    $redis->sAdd('key1' , 'set1');
    $redis->sAdd('key1' , 'set2');
    $redis->sAdd('key1' , 'set3');// 'key1' => {'set3', 'set1', 'set2'}
    
    $redis->sPop('key1');// 'set1', 'key1' => {'set3', 'set2'}
    $redis->sPop('key1');// 'set3', 'key1' => {'set2'}

#### srandmember key ####

作用: 返回集合key中,随机的1个元素.

<?php
    $redis->sAdd('key1' , 'set1');
    $redis->sAdd('key1' , 'set2');
    $redis->sAdd('key1' , 'set3');// 'key1' => {'set3', 'set1', 'set2'}
    
    $redis->sRandMember('key1');// 'set1', 'key1' => {'set3', 'set1', 'set2'}
    $redis->sRandMember('key1');// 'set3', 'key1' => {'set3', 'set1', 'set2'}

#### sismember key value ####

作用: 判断value是否在key集合中  
是返回1,否返回0

<?php
    $redis->sAdd('key1' , 'set1');
    $redis->sAdd('key1' , 'set2');
    $redis->sAdd('key1' , 'set3');//'key1' => {'set1', 'set2', 'set3'}
    
    $redis->sIsMember('key1', 'set1');//TRUE
    $redis->sIsMember('key1', 'setX');//FALSE

#### smembers key ####

作用: 返回集中中所有的元素

<?php
    $redis->delete('s');
    $redis->sAdd('s', 'a');
    $redis->sAdd('s', 'b');
    $redis->sAdd('s', 'a');
    $redis->sAdd('s', 'c');
    
    var_dump($redis->sMembers('s'));//array(3) {[0]=>string(1) "c" [1]=>string(1) "a" [2]=>string(1) "b"}
    //集合顺序是随机的，对应于Redis本身内部的结构表征。

#### scard key ####

作用: 返回集合中元素的个数

<?php
    $redis->sAdd('key1' , 'set1');
    $redis->sAdd('key1' , 'set2');
    $redis->sAdd('key1' , 'set3');// 'key1' => {'set1', 'set2', 'set3'}
    $redis->sCard('key1');// 3
    $redis->sCard('keyX');// 0

#### smove source dest value ####

作用:把source中的value删除,并添加到dest集合中

<?php
    $redis->sAdd('key1' , 'set11');
    $redis->sAdd('key1' , 'set12');
    $redis->sAdd('key1' , 'set13');// 'key1' => {'set11', 'set12', 'set13'}
    
    $redis->sAdd('key2' , 'set21');
    $redis->sAdd('key2' , 'set22');// 'key2' => {'set21', 'set22'}
    
    $redis->sMove('key1', 'key2', 'set13');
    // 'key1' => {'set11', 'set12'}
    // 'key2' => {'set21', 'set22', 'set13'}

#### sinter key1 key2 key3 ####

作用: 求出key1 key2 key3 三个集合中的交集,并返回

redis 127.0.0.1:6379> sadd s1 0 2 4 6
    (integer) 4
    redis 127.0.0.1:6379> sadd s2 1 2 3 4
    (integer) 4
    redis 127.0.0.1:6379> sadd s3 4 8 9 12
    (integer) 4
    redis 127.0.0.1:6379> sinter s1 s2 s3
    1) "4"
    redis 127.0.0.1:6379> sinter s3 s1 s2
    1)"4"

<?php
    $redis->sAdd('key1', 'val1');
    $redis->sAdd('key1', 'val2');
    $redis->sAdd('key1', 'val3');
    $redis->sAdd('key1', 'val4');
    
    $redis->sAdd('key2', 'val3');
    $redis->sAdd('key2', 'val4');
    
    $redis->sAdd('key3', 'val3');
    $redis->sAdd('key3', 'val4');
    
    var_dump($redis->sInter('key1', 'key2', 'key3'));
    //array(2) {[0]=>string(4) "val4" [1]=>string(4) "val3"}

#### sinterstore dest key1 key2 key3 ####

作用: 求出key1 key2 key3 三个集合中的交集,并赋给dest

<?php
    $redis->sAdd('key1', 'val1');
    $redis->sAdd('key1', 'val2');
    $redis->sAdd('key1', 'val3');
    $redis->sAdd('key1', 'val4');
    
    $redis->sAdd('key2', 'val3');
    $redis->sAdd('key2', 'val4');
    
    $redis->sAdd('key3', 'val3');
    $redis->sAdd('key3', 'val4');
    
    var_dump($redis->sInterStore('dest', 'key1', 'key2', 'key3'));//int(2)
    var_dump($redis->sMembers('dest'));
    //array(2) {[0]=>string(4) "val4" [1]=>string(4) "val3"}

#### sunion key1 key2.. Keyn ####

作用: 求出key1 key2 keyn的并集,并返回

<?php
    $redis->sAdd('s0', '1');
    $redis->sAdd('s0', '2');
    $redis->sAdd('s1', '3');
    $redis->sAdd('s1', '1');
    $redis->sAdd('s2', '3');
    $redis->sAdd('s2', '4');
    
    var_dump($redis->sUnion('s0', 's1', 's2'));
    //array(4) { [0]=> string(1) "3" [1]=> string(1) "4" [2]=> string(1) "1" [3]=> string(1) "2"}

#### sdiff key1 key2 key3 ####

作用: 求出key1与key2 key3的差集  
即key1-key2-key3

<?php
    $redis->delete('s0', 's1', 's2');
    
    $redis->sAdd('key1'1'); $redis->sAdd('key1'2');
    $redis->sAdd('key1'3'); $redis->sAdd('key1'4');
    
    $redis->sAdd('key2', '1');
    $redis->sAdd('key3', '3');
    
    var_dump($redis->sDiff('key1', 'key2', 'key3'));
    //array(2) {[0]=> string(1) "4" [1]=> string(1) "2"}