Redis learning notes - geographic information location (GEO)

Redis3.2 Version provides GEO（ Location of geographic information ） function , Support the storage of geographic location information to realize such as nearby location 、 Shake this kind of function that depends on Geographic Information , It is a great blessing for developers who need to implement these functions

Add location information

geoadd key longitude latitude member [longitude latitude member ...]

longitude、latitude、member They are the longitude of the geographical location 、 latitude 、 member

Add location information of Beijing

127.0.0.1:6379> geoadd cities 116.28 39.55 beijing
(integer) 1

If the addition is successful, return 1, Exists and will return 0, If you are modifying, you can also use geoadd, return 0

Add the location information of three cities Tianjin at the same time 、 Shanghai and Chongqing

127.0.0.1:6379> geoadd cities 117.12 39.08 tianjin 121.47 31.23 shanghai 106.55 29.57 chongqing
(integer) 3

Get geographic location information

geopos key member [member ...]

Get the location information of Shanghai , Get the location information of Shanghai and Chongqing at the same time

127.0.0.1:6379> geopos cities shanghai
1) 1) "121.47000163793563843"
   2) "31.22999903975783553"
127.0.0.1:6379> geopos cities shanghai chongqing
1) 1) "121.47000163793563843"
   2) "31.22999903975783553"
2) 1) "106.5499994158744812"
   2) "29.5700000136221135"

Gets the distance between two geographical locations

geodist key member1 member2 [unit]

unit Representative unit , If it is not filled in, the default return company is m（ rice ）; You can enter the following four units

• m（meters） It's for rice
• km（kilometers） Representative kilometer
• mi（miles） For miles
• ft（feet） For ruler

Get the distance between Shanghai and Chongqing

127.0.0.1:6379> geodist cities shanghai chongqing
"1442064.7968"
127.0.0.1:6379> geodist cities shanghai chongqing km
"1442.0648"

Gets the collection of geographic information locations within the specified location range

georadius key longitude latitude radiusm|km|ft|mi [withcoord] [withdist] [withhash] [COUNT count] [asc|desc] [store key] [storedist key]

georadiusbymember key member radiusm|km|ft|mi [withcoord] [withdist] [withhash] [COUNT count] [asc|desc] [store key] [storedist key]

georadius and georadiusbymember The effect of the two commands is the same , All calculate other geographic information locations within the specified radius with one geographic location as the center , The difference is georadius The center position of the command gives the specific longitude and latitude ,georadiusbymember Just give the members . among radiusm|km|ft|mi Is the required parameter , The radius is specified （ With units ）, These two commands have many optional parameters , As shown below

• withcoord： The return result contains latitude and longitude
• withdist： The return result contains the distance from the center node position
• withhash： The return result contains geohash, of geohash Later on
• COUNT count： Specify the number of returned results
• asc|desc： The returned results are in ascending or descending order according to the distance from the central node
• store key： Save the geographic location information of the returned result to the specified key
• storedist key： Save the distance between the returned result and the central node to the specified key

Get Beijing 1200km The cities within

127.0.0.1:6379>  georadiusbymember cities beijing 1200 km
1) "beijing"
2) "tianjin"
3) "shanghai"

obtain geohash

geohash key member [member ...]

Redis Use geohash Convert two-dimensional latitude and longitude to one-dimensional string , The following operation will return beijing Of geohash value

127.0.0.1:6379> geohash cities beijing
1) "wx48ypbe2q0"

Delete geographic information

GEO There is no command to delete members , But because GEO The underlying implementation of zset, So you can borrow zrem Command to delete geographic location information

zrem key member

Delete location information of Beijing

127.0.0.1:6379> zrem cities beijing
(integer) 1