GEOHASH key member [member ...]

Redis geohash 用于返回一个或多个位置元素的 Geohash 表示。Redis GEO 使用 geohash 来保存地理位置的坐标。

*语法

geohash 语法格式如下：

GEOHASH key member [member ...]

*Geohash string properties

The command returns 11 characters Geohash strings, so no precision is loss compared to the Redis internal 52 bit representation. The returned Geohashes have the following properties:

  1. They can be shortened removing characters from the right. It will lose precision but will still point to the same area.
  2. It is possible to use them in geohash.org URLs such as http://geohash.org/<geohash-string>. This is an example of such URL.
  3. Strings with a similar prefix are nearby, but the contrary is not true, it is possible that strings with different prefixes are nearby too.

*返回值

数组:一个数组， 数组的每个项都是一个 geohash 。 命令返回的 geohash 的位置与用户给定的位置元素的位置一一对应。

*例子

redis>  GEOADD Sicily 13.361389 38.115556 "Palermo" 15.087269 37.502669 "Catania" 
(integer) 2
redis>  GEOHASH Sicily Palermo Catania 
1) "sqc8b49rny0"
2) "sqdtr74hyu0"
redis> 

可用版本>= 3.2.0.

时间复杂度: O(log(N))，其中N是有序集合中的元素数。