Work with Geospatial Data
On this page
Overview
In this guide, you can learn how to work with geospatial data; data formats, indexes, and queries. Geospatial data represents a geographic location on the surface of the Earth, or data on a Euclidean plane.
Examples of geospatial data include:
Locations of movie theaters
Borders of countries
Routes of bicycle rides
Dog exercise areas in New York City
Points on a graph
Store Geospatial Data
All geospatial data in MongoDB is stored in one of the following formats:
GeoJSON, a format that represents geospatial data on an earth-like sphere.
Legacy Coordinate Pair, a format that represents geospatial data on a Euclidean plane.
GeoJSON
Use GeoJSON to store data that represents geospatial information on an earth-like sphere. GeoJSON is composed of one or more positions and a type.
Positions
A position represents a single place on Earth and exists in code as an array containing the following values:
Longitude in the first position (required)
Latitude in the second position (required)
Elevation in the third position (optional)
The following is the position of the MongoDB Headquarters in New York City, NY.
[]float64{-73.986805, 40.7620853}
Important
Longitude then Latitude
GeoJSON orders coordinates as longitude first and latitude second. This may be surprising as geographic coordinate system conventions generally list latitude first and longitude second. Make sure to check what format any other tools you are working with use. Popular tools such as OpenStreetMap and Google Maps list coordinates as latitude first and longitude second.
Types
Your GeoJSON object's type determines the geometric shape it represents. Geometric shapes are made up of positions.
Here are some common GeoJSON types and how you can specify them with positions:
Point
: a single position. The followingPoint
represents the location of the MongoDB Headquarters:bson.D{ {"name", "MongoDB HQ"}, {"location", bson.D{ {"type", "Point"}, {"coordinates", []float64{-73.986805, 40.7620853}}, }}, } LineString
: an array of two or more positions that forms a series of line segments. ALineString
can represent a path, route, border, or any other linear geospatial data. The followingLineString
represents a segment of the Great Wall of China:bson.D{ {"name", "Great Wall of China"}, {"location", bson.D{ {"type", "LineString"}, {"coordinates", [][]float64{ {116.572, 40.430}, {116.570, 40.434}, {116.567, 40.436}, {116.566, 40.441}, }}}, }, } Polygon
: an array of positions in which the first and last position are the same and enclose some space. The followingPolygon
represents the land within Vatican City:bson.D{ {"name", "Vatican City"}, {"location", bson.D{ {"type", "Polygon"}, {"coordinates", [][][]float64{{ {12.446086, 41.901977}, {12.457952, 41.901559}, {12.455375, 41.907351}, {12.449863, 41.905186}, {12.446086, 41.901977}, }}}, }}, }
To learn more about the GeoJSON types you can use in MongoDB, see the GeoJSON manual entry.
For definitive information on GeoJSON, see the official IETF specification.
Legacy Coordinate Pairs
Use legacy coordinate pairs to store data that represents geospatial information on a two-dimensional Euclidean plane.
Your field should contain an array of two values in which the first represents
the x
axis value and the second represents the y
axis value.
bson.D{{"center", []int16{0, 0}}}
For more information on legacy coordinate pairs, see the MongoDB server manual page on legacy coordinate pairs.
Geospatial Indexes
To enable querying on geospatial data, you must create an index that corresponds to the data format. The following index types enable geospatial queries:
2dsphere
for GeoJSON data2d
for legacy coordinate pairs
2dsphere
To query data stored in the GeoJSON format, add the field containing
both the type
and coordinates
to a 2dsphere
index. The
following example creates a 2dsphere
index on the location
field:
indexModel := mongo.IndexModel{ Keys: bson.D{{"location", "2dsphere"}}, } name, err := coll.Indexes().CreateOne(context.TODO(), indexModel) if err != nil { panic(err) }
2d
To query data stored as legacy coordinate pairs, you must add the field containing
legacy coordinate pairs to a 2d
index. The following example creates a
2d
index on the coordinates
field:
indexModel := mongo.IndexModel{ Keys: bson.D{{"location.coordinates", "2d"}}, } name, err := coll.Indexes().CreateOne(context.TODO(), indexModel) if err != nil { panic(err) }
Geospatial Queries
To perform a geospatial query, create a query filter with a field name and a geospatial query operator. You can specify additional options for certain geospatial query operators to limit the documents returned.
If you have not done so, you must create a geospatial index to enable geospatial queries.
Tip
Supported Operators
Spherical (2dsphere
) and flat (2d
) indexes support some, but
not all, of the same query operators. For a full list of operators
and their index compatibility, see the
manual entry for geospatial queries.
Query Operators
To query your geospatial data, use one of the following query operators:
$near
$geoWithin
$nearSphere
$geoIntersects
requires a 2dsphere index
When using the $near
operator, you can specify the following distance operators:
$minDistance
$maxDistance
When using the $geoWithin
operator, you can specify the following shape operators:
$box
$polygon
$center
$centerSphere
For more information on geospatial query operators, see the manual entry for geospatial queries.
Examples
The following examples use the MongoDB Atlas sample dataset. You can load sample datasets into your database on the free tier of MongoDB Atlas by following the Get Started with Atlas Guide or you can import the sample dataset into a local MongoDB instance.
The examples use the theaters
collection in the sample_mflix
database
from the sample dataset. The theaters
collection contains a 2dsphere
index
on the location.geo
field.
Query by Proximity
The following example queries for documents with a location.geo
field
within 1000 meters of the MongoDB Headquarters in New York City, NY. It returns documents
from nearest to farthest.
mongoDBHQ := bson.D{{"type", "Point"}, {"coordinates", []float64{-73.986805, 40.7620853}}} filter := bson.D{ {"location.geo", bson.D{ {"$near", bson.D{ {"$geometry", mongoDBHQ}, {"$maxDistance", 1000}, }}, }}, } var places []bson.D output, err := coll.Find(context.TODO(), filter) if err = output.All(context.TODO(), &places); err != nil { panic(err) } for _, place := range places { res, _ := bson.MarshalExtJSON(place, false, false) fmt.Println(string(res)) }
{"_id":{...},"theaterId":1908,"location":{"address":{...},"geo":{"type":"Point","coordinates":[-73.983487,40.76078]}}} {"_id":{...},"theaterId":1448,"location":{"address":{...},"geo":{"type":"Point","coordinates":[-73.982094,40.769882]}}}
Query Within a Range
The following example queries for documents with a location.geo
field
no closer than 2000 meters and no farther than 3000 meters of the MongoDB
Headquarters in New York City, NY. It returns documents from nearest to farthest.
mongoDBHQ := bson.D{{"type", "Point"}, {"coordinates", []float64{-73.986805, 40.7620853}}} filter := bson.D{ {"location.geo", bson.D{ {"$nearSphere", bson.D{ {"$geometry", mongoDBHQ}, {"$minDistance", 2000}, {"$maxDistance", 3000}, }}, }}, } var places []bson.D output, err := coll.Find(context.TODO(), filter) if err = output.All(context.TODO(), &places); err != nil { panic(err) } for _, place := range places { res, _ := bson.MarshalExtJSON(place, false, false) fmt.Println(string(res)) }
{"_id":{...},"theaterId":482,"location":{...},"geo":{"type":"Point","coordinates":[-73.99295,40.74194]}}}
Additional Resources
For more information about working with geospatial data, see the manual entry for geospatial data.
For more information about supported GeoJSON types, see the the GeoJSON manual entry.
For more information about geospatial query operators, see the manual entry for geospatial queries.
For more information about working with indexes with the Go driver, see the index guide.