ZSET(stored set)和 set 一样是字符串的集合，不同的是每个元素都会关联一个 double 类型的 score 。实现使用的是 skip list 和 hash table ， skip list 的实现使用的是双线链表。 Score 的主要作用是排序，因此 sorted set 主要用作索引。
zAdd
Description
Adds the specified member with a given score to the sorted set stored at key.
增加一个或多个元素，如果该元素已经存在，更新它的socre值
虽然有序集合有序，但它也是集合，不能重复元素，添加重复元素只会
更新原有元素的score值
Parameters
key
score : double
value: string
Return value
Long 1 if the element is added. 0 otherwise.
Example
$redis->zAdd('key', 1, 'val1'); $redis->zAdd('key', 0, 'val0'); $redis->zAdd('key', 5, 'val5'); $redis->zRange('key', 0, -1); // array(val0, val1, val5)
zRange
Description
Returns a range of elements from the ordered set stored at the specified key, with values in the range [start, end]. start and stop are interpreted as zero-based indices: 0 the first element, 1 the second ... -1 the last element, -2 the penultimate ...
取得特定范围内的排序元素,0代表第一个元素,1代表第二个以此类推。-1代表最后一个,-2代表倒数第二个...
Parameters
key
start: long
end: long
withscores: bool = false
Return value
Array containing the values in specified range.
Example
$redis->zAdd('key1', 0, 'val0'); $redis->zAdd('key1', 2, 'val2'); $redis->zAdd('key1', 10, 'val10'); $redis->zRange('key1', 0, -1); /* array('val0', 'val2', 'val10') */ // with scores $redis->zRange('key1', 0, -1, true); /* array('val0' => 0, 'val2' => 2, 'val10' => 10) */
zDelete, zRem
Description
Deletes a specified member from the ordered set.
从有序集合中删除指定的成员。
Parameters
key
member
Return value
LONG 1 on success, 0 on failure.
Example
$redis->zAdd('key', 0, 'val0'); $redis->zAdd('key', 2, 'val2'); $redis->zAdd('key', 10, 'val10'); $redis->zDelete('key', 'val2'); $redis->zRange('key', 0, -1); /* array('val0', 'val10') */
zRevRange
Description
Returns the elements of the sorted set stored at the specified key in the range [start, end] in reverse order. start and stop are interpretated as zero-based indices: 0 the first element, 1 the second ... -1 the last element, -2 the penultimate ...
返回key对应的有序集合中指定区间的所有元素。这些元素按照score从高到低的顺序进行排列。对于具有相同的score的元素而言，将会按照递减的字典顺序进行排列。该命令与ZRANGE类似，只是该命令中元素的排列顺序与前者不同。
Parameters
key
start: long
end: long
withscores: bool = false
Return value
Array containing the values in specified range.
Example
$redis->zAdd('key', 0, 'val0'); $redis->zAdd('key', 2, 'val2'); $redis->zAdd('key', 10, 'val10'); $redis->zRevRange('key', 0, -1); /* array('val10', 'val2', 'val0') */ // with scores $redis->zRevRange('key', 0, -1, true); /* array('val10' => 10, 'val2' => 2, 'val0' => 0) */
zRangeByScore, zRevRangeByScore
Description
Returns the elements of the sorted set stored at the specified key which have scores in the range [start,end]. Adding a parenthesis before start or end excludes it from the range. +inf and -inf are also valid limits. zRevRangeByScore returns the same items in reverse order, when the start and end parameters are swapped.
返回key对应的有序集合中score介于min和max之间的所有元素（包哈score等于min或者max的元素）。元素按照score从低到高的顺序排列。如果元素具有相同的score，那么会按照字典顺序排列。
可选的选项LIMIT可以用来获取一定范围内的匹配元素。如果偏移值较大，有序集合需要在获得将要返回的元素之前进行遍历，因此会增加O(N)的时间复杂度。可选的选项WITHSCORES可以使得在返回元素的同时返回元素的score，该选项自从Redis 2.0版本后可用。
Parameters
key
start: string
end: string
options: array
Two options are available: withscores => TRUE, and limit => array($offset, $count)
Return value
Array containing the values in specified range.
Example
$redis->zAdd('key', 0, 'val0'); $redis->zAdd('key', 2, 'val2'); $redis->zAdd('key', 10, 'val10'); $redis->zRangeByScore('key', 0, 3); /* array('val0', 'val2') */ $redis->zRangeByScore('key', 0, 3, array('withscores' => TRUE); /* array('val0' => 0, 'val2' => 2) */ $redis->zRangeByScore('key', 0, 3, array('limit' => array(1, 1)); /* array('val2' => 2) */ $redis->zRangeByScore('key', 0, 3, array('limit' => array(1, 1)); /* array('val2') */ $redis->zRangeByScore('key', 0, 3, array('withscores' => TRUE, 'limit' => array(1, 1)); /* array('val2' => 2) */
zCount
Description
Returns the number of elements of the sorted set stored at the specified key which have scores in the range [start,end]. Adding a parenthesis before start or end excludes it from the range. +inf and -inf are also valid limits.
返回key对应的有序集合中介于min和max间的元素的个数。
Parameters
key
start: string
end: string
Return value
LONG the size of a corresponding zRangeByScore.
Example
$redis->zAdd('key', 0, 'val0'); $redis->zAdd('key', 2, 'val2'); $redis->zAdd('key', 10, 'val10'); $redis->zCount('key', 0, 3); /* 2, corresponding to array('val0', 'val2') */
zRemRangeByScore, zDeleteRangeByScore
Description
Deletes the elements of the sorted set stored at the specified key which have scores in the range [start,end].
移除key对应的有序集合中scroe位于min和max（包含端点）之间的所哟元素。从2.1.6版本后开始，区间端点min和max可以被排除在外，这和ZRANGEBYSCORE的语法一样。
Parameters
key
start: double or "+inf" or "-inf" string
end: double or "+inf" or "-inf" string
Return value
LONG The number of values deleted from the sorted set
Example
$redis->zAdd('key', 0, 'val0'); $redis->zAdd('key', 2, 'val2'); $redis->zAdd('key', 10, 'val10'); $redis->zRemRangeByScore('key', 0, 3); /* 2 */
zRemRangeByRank, zDeleteRangeByRank
Description
Deletes the elements of the sorted set stored at the specified key which have rank in the range [start,end].
移除key对应的有序集合中rank值介于start和stop之间的所有元素。start和stop均是从0开始的，并且两者均可以是负值。当索引值为负值时，表明偏移值从有序集合中score值最高的元素开始。例如：-1表示具有最高score的元素，而-2表示具有次高score的元素，以此类推。
Parameters
key
start: LONG
end: LONG
Return value
LONG The number of values deleted from the sorted set
Example
$redis->zAdd('key', 1, 'one'); $redis->zAdd('key', 2, 'two'); $redis->zAdd('key', 3, 'three'); $redis->zRemRangeByRank('key', 0, 1); /* 2 */ $redis->zRange('key', 0, -1, array('withscores' => TRUE)); /* array('three' => 3) */
zSize, zCard
Description
Returns the cardinality of an ordered set.
返回存储在key对应的有序集合中的元素的个数。
Parameters
key
Return value
Long, the set's cardinality
Example
$redis->zAdd('key', 0, 'val0'); $redis->zAdd('key', 2, 'val2'); $redis->zAdd('key', 10, 'val10'); $redis->zSize('key'); /* 3 */
zScore
Description
Returns the score of a given member in the specified sorted set.
返回key对应的有序集合中member的score值。如果member在有序集合中不存在，那么将会返回nil。
Parameters
key
member
Return value
Double
Example
$redis->zAdd('key', 2.5, 'val2'); $redis->zScore('key', 'val2'); /* 2.5 */
zRank, zRevRank
Description
Returns the rank of a given member in the specified sorted set, starting at 0 for the item with the smallest score. zRevRank starts at 0 for the item with the largest score.
返回key对应的有序集合中member元素的索引值，元素按照score从低到高进行排列。rank值（或index）是从0开始的，这意味着具有最低score值的元素的rank值为0。使用ZREVRANK可以获得从高到低排列的元素的rank（或index）。
Parameters
key
member
Return value
Long, the item's score.
Example
$redis->delete('z'); $redis->zAdd('key', 1, 'one'); $redis->zAdd('key', 2, 'two'); $redis->zRank('key', 'one'); /* 0 */ $redis->zRank('key', 'two'); /* 1 */ $redis->zRevRank('key', 'one'); /* 1 */ $redis->zRevRank('key', 'two'); /* 0 */
zIncrBy
Description
Increments the score of a member from a sorted set by a given amount.
将key对应的有序集合中member元素的scroe加上increment。如果指定的member不存在，那么将会添加该元素，并且其score的初始值为increment。如果key不存在，那么将会创建一个新的有序列表，其中包含member这一唯一的元素。如果key对应的值不是有序列表，那么将会发生错误。指定的score的值应该是能够转换为数字值的字符串，并且接收双精度浮点数。同时，你也可用提供一个负值，这样将减少score的值。
Parameters
key
value: (double) value that will be added to the member's score
member
Return value
DOUBLE the new value
Examples
$redis->delete('key'); $redis->zIncrBy('key', 2.5, 'member1'); /* key or member1 didn't exist, so member1's score is to 0 before the increment */ /* and now has the value 2.5 */ $redis->zIncrBy('key', 1, 'member1'); /* 3.5 */
zUnion
Description
Creates an union of sorted sets given in second argument. The result of the union will be stored in the sorted set defined by the first argument. The third optionnel argument defines weights to apply to the sorted sets in input. In this case, the weights will be multiplied by the score of each element in the sorted set before applying the aggregation. The forth argument defines the AGGREGATEoption which specify how the results of the union are aggregated.
对keys对应的numkeys个有序集合计算合集，并将结果存储在destination中。在传递输入keys之前必须提供输入keys的个数和其它可选参数。在默认情况下，元素的结果score是包含该元素的所有有序集合中score的和。如果使用WEIGHTS选项，你可以对每一个有序集合指定一个操作因子。这意味着每一个有序集合中的每个元素的score在传递给聚合函数之前均会被乘以该因子。当WEIGHTS没有指定时，操作因子默认为1。
使用AGGREGATE选项，你可以指定交集中的结果如何被聚合。该选项默认值为SUM，在这种情况下，一个元素的所有score值均会被相加。当选项被设置为MIN或MAX时，结果集合中将会包含一个元素的最大或者最小的score值。如果destination已经存在，那么它将会被重写。
Parameters
keyOutput
arrayZSetKeys
arrayWeights
aggregateFunction Either "SUM", "MIN", or "MAX": defines the behaviour to use on duplicate entries during the zUnion.
Return value
LONG The number of values in the new sorted set.
Example
$redis->delete('k1'); $redis->delete('k2'); $redis->delete('k3'); $redis->delete('ko1'); $redis->delete('ko2'); $redis->delete('ko3'); $redis->zAdd('k1', 0, 'val0'); $redis->zAdd('k1', 1, 'val1'); $redis->zAdd('k2', 2, 'val2'); $redis->zAdd('k2', 3, 'val3'); $redis->zUnion('ko1', array('k1', 'k2')); /* 4, 'ko1' => array('val0', 'val1', 'val2', 'val3') */ /* Weighted zUnion */ $redis->zUnion('ko2', array('k1', 'k2'), array(1, 1)); /* 4, 'ko1' => array('val0', 'val1', 'val2', 'val3') */ $redis->zUnion('ko3', array('k1', 'k2'), array(5, 1)); /* 4, 'ko1' => array('val0', 'val2', 'val3', 'val1') */
zInter
Description
Creates an intersection of sorted sets given in second argument. The result of the union will be stored in the sorted set defined by the first argument. The third optionnel argument defines weights to apply to the sorted sets in input. In this case, the weights will be multiplied by the score of each element in the sorted set before applying the aggregation. The forth argument defines the AGGREGATEoption which specify how the results of the union are aggregated.
计算numkeys个由keys指定的有序集合的交集，并且将结果存储在destination中。在该命令中，在你传递输入keys之前，必须提供输入keys的个数和其它可选的参数。
在默认情况下，一个元素的结果score是具有该元素的所有有序集合的score的和。关于WEIGHTS和AGGREGATE选项，可以参看ZUNIONSTORE命令。如果目标已经存在，那么它将会被重写。
Parameters
keyOutput
arrayZSetKeys
arrayWeights
aggregateFunction Either "SUM", "MIN", or "MAX": defines the behaviour to use on duplicate entries during the zInter.
Return value
LONG The number of values in the new sorted set.
Example
$redis->delete('k1'); $redis->delete('k2'); $redis->delete('k3'); $redis->delete('ko1'); $redis->delete('ko2'); $redis->delete('ko3'); $redis->delete('ko4'); $redis->zAdd('k1', 0, 'val0'); $redis->zAdd('k1', 1, 'val1'); $redis->zAdd('k1', 3, 'val3'); $redis->zAdd('k2', 2, 'val1'); $redis->zAdd('k2', 3, 'val3'); $redis->zInter('ko1', array('k1', 'k2')); /* 2, 'ko1' => array('val1', 'val3') */ $redis->zInter('ko2', array('k1', 'k2'), array(1, 1)); /* 2, 'ko2' => array('val1', 'val3') */ /* Weighted zInter */ $redis->zInter('ko3', array('k1', 'k2'), array(1, 5), 'min'); /* 2, 'ko3' => array('val1', 'val3') */ $redis->zInter('ko4', array('k1', 'k2'), array(1, 5), 'max'); /* 2, 'ko4' => array('val3', 'val1') */