Spatial Index

Overview

A spatial index enables efficient radius queries on POINT and POINT3D properties using geohash-based encoding. Instead of scanning all entities and computing distances, the spatial index narrows the search to a small set of candidates within the relevant geographic area.

Spatial indexes support:

• POINT: WGS84 geographic coordinates (latitude, longitude) for 2D spatial queries.
• POINT3D: 3D Cartesian coordinates (x, y, z) for 3D spatial queries.

Showing Spatial Indexes

Spatial indexes appear in the standard index listing:

GQL
SHOW NODE INDEX
SHOW EDGE INDEX

Spatial indexes are displayed with type SPATIAL and the expression function geohash.

Creating a Spatial Index

GQL
CREATE SPATIAL INDEX <indexName> ON NODE <schemaName> (<propertyName>)
CREATE SPATIAL INDEX <indexName> ON EDGE <schemaName> (<propertyName>)

The property must be of type POINT or POINT3D. Attempting to create a spatial index on other property types returns an error.

To create a spatial index on a POINT property:

GQL
CREATE SPATIAL INDEX idx_location ON NODE Station (location)

To create a spatial index on a POINT3D property:

GQL
CREATE SPATIAL INDEX idx_position ON NODE Sensor (position)

To create a spatial index on an edge property:

GQL
CREATE SPATIAL INDEX idx_route ON EDGE Route (waypoint)

Using IF NOT EXISTS

GQL
CREATE SPATIAL INDEX idx_location ON NODE Station (location) IF NOT EXISTS

Dropping a Spatial Index

GQL
DROP NODE SPATIAL INDEX idx_location
DROP EDGE SPATIAL INDEX idx_route

Using IF EXISTS

GQL
DROP NODE SPATIAL INDEX idx_location IF EXISTS
DROP EDGE SPATIAL INDEX idx_route IF EXISTS

Using Spatial Indexes

When a spatial index exists on a property, distance() queries with < or <= operators are automatically optimized to use spatial index range scans instead of full table scans.

Optimized Query Patterns

Basic radius query:

GQL
MATCH (n:Station)
WHERE distance(n.location, point({latitude: 31.23, longitude: 121.47})) < 50000
RETURN n.name

Less-than-or-equal radius query:

GQL
MATCH (n:Station)
WHERE distance(n.location, point({latitude: 31.23, longitude: 121.47})) <= 50000
RETURN n.name

Reversed argument order (also optimized):

GQL
MATCH (n:Station)
WHERE distance(point({latitude: 31.23, longitude: 121.47}), n.location) < 50000
RETURN n.name

Combined with other conditions:

GQL
MATCH (n:Station)
WHERE distance(n.location, point({latitude: 31.23, longitude: 121.47})) < 50000
  AND n.name STARTS WITH 'S'
RETURN n.name

3D distance query:

GQL
MATCH (n:Sensor)
WHERE distance(n.position, point3d({x: 115.0, y: 215.0, z: 65.0})) < 20
RETURN n.name

Use EXPLAIN to verify that a spatial index is being used:

GQL
EXPLAIN MATCH (n:Station)
WHERE distance(n.location, point({latitude: 31.23, longitude: 121.47})) < 50000
RETURN n

The execution plan will show SPATIAL INDEX SCAN when the spatial index is used.

Not Optimized

The following patterns do not use spatial indexes and result in a full scan:

• Greater-than comparisons: distance(...) > 50000
• Expressions that modify the distance: distance(...) + 100 < 50000

DML Auto-Maintenance

Spatial indexes are automatically maintained when data changes:

Entities with NULL spatial properties are not indexed.