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GEORADIUS

GEORADIUS key longitude latitude radius m|km|ft|mi [WITHCOORD] [WITHDIST] [WITHHASH] [COUNT count] [ASC|DESC] [STORE key] [STOREDIST key]

Available since 3.2.0.

Time complexity: O(N+log(M)) where N is the number of elements inside the bounding box of the circular area delimited by center and radius and M is the number of items inside the index.

Return the members of a sorted set populated with geospatial information using GEOADD, which are within the borders of the area specified with the center location and the maximum distance from the center (the radius).

This manual page also covers the GEORADIUS_RO and GEORADIUSBYRANGE_RO variants (see the section below for more information).

The common use case for this command is to retrieve geospatial items near a specified point and no far than a given amount of meters (or other units). This allows, for example, to suggest mobile users of an application nearby places.

The radius is specified in one of the following units:

m for meters.
km for kilometers.
mi for miles.
ft for feet.

The command optionally returns additional information using the following options:

WITHDIST: Also return the distance of the returned items from the specified center. The distance is returned in the same unit as the unit specified as the radius argument of the command.
WITHCOORD: Also return the longitude,latitude coordinates of the matching items.
WITHHASH: Also return the raw geohash-encoded sorted set score of the item, in the form of a 52 bit unsigned integer. This is only useful for low level hacks or debugging and is otherwise of little interest for the general user.

The command default is to return unsorted items. Two different sorting methods can be invoked using the following two options:

ASC: Sort returned items from the nearest to the farthest, relative to the center.
DESC: Sort returned items from the farthest to the nearest, relative to the center.

By default all the matching items are returned. It is possible to limit the results to the first N matching items by using the COUNT <count> option. However note that internally the command needs to perform an effort proportional to the number of items matching the specified area, so to query very large areas with a very small COUNT option may be slow even if just a few results are returned. On the other hand COUNT can be a very effective way to reduce bandwidth usage if normally just the first results are used.

Return value

Array reply, specifically:

Without any WITH option specified, the command just returns a linear array like ["New York","Milan","Paris"].
If WITHCOORD, WITHDIST or WITHHASH options are specified, the command returns an array of arrays, where each sub-array represents a single item.

When additional information is returned as an array of arrays for each item, the first item in the sub-array is always the name of the returned item. The other information is returned in the following order as successive elements of the sub-array.

The distance from the center as a floating point number, in the same unit specified in the radius.
The geohash integer.
The coordinates as a two items x,y array (longitude,latitude).

So for example the command GEORADIUS Sicily 15 37 200 km WITHCOORD WITHDIST will return each item in the following way:

["Palermo","190.4424",["13.361389338970184","38.115556395496299"]]

Read only variants

Since GEORADIUS and GEORADIUSBYMEMBER have a STORE and STOREDIST option they are technically flagged as writing commands in the Redis command table. For this reason read-only slaves will flag them, and Redis Cluster slaves will redirect them to the master instance even if the connection is in read only mode (See the READONLY command of Redis Cluster).

Breaking the compatibility with the past was considered but rejected, at least for Redis 4.0, so instead two read only variants of the commands were added. They are exactly like the original commands but refuse the STORE and STOREDIST options. The two variants are called GEORADIUS_RO and GEORADIUSBYMEMBER_RO, and can safely be used in slaves.

Both commands were introduced in Redis 3.2.10 and Redis 4.0.0 respectively.

Examples

redis> GEOADD Sicily 13.361389 38.115556 "Palermo" 15.087269 37.502669 "Catania" (integer) 2 redis> GEORADIUS Sicily 15 37 200 km WITHDIST

1) 1) "Palermo"
   2) "190.4424"
2) 1) "Catania"
   2) "56.4413"

redis> GEORADIUS Sicily 15 37 200 km WITHCOORD

1) 1) "Palermo"
   2) 1) "13.36138933897018433"
      2) "38.11555639549629859"
2) 1) "Catania"
   2) 1) "15.08726745843887329"
      2) "37.50266842333162032"

redis> GEORADIUS Sicily 15 37 200 km WITHDIST WITHCOORD

1) 1) "Palermo"
   2) "190.4424"
   3) 1) "13.36138933897018433"
      2) "38.11555639549629859"
2) 1) "Catania"
   2) "56.4413"
   3) 1) "15.08726745843887329"
      2) "37.50266842333162032"

© 2009–2017 Salvatore Sanfilippo
Licensed under the Creative Commons Attribution-ShareAlike License 4.0.
https://redis.io/commands/georadius