druid/docs/development/geo.md

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---
id: geo
title: "Spatial filters"
---
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Apache Druid (incubating) supports filtering specially spatially indexed columns based on an origin and a bound.
## Spatial indexing
In any of the data specs, there is the option of providing spatial dimensions. For example, for a JSON data spec, spatial dimensions can be specified as follows:
```json
{
"type": "hadoop",
"dataSchema": {
"dataSource": "DatasourceName",
"parser": {
"type": "string",
"parseSpec": {
"format": "json",
"timestampSpec": {
"column": "timestamp",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [],
"spatialDimensions": [{
"dimName": "coordinates",
"dims": ["lat", "long"]
}]
}
}
}
}
}
```
## Spatial filters
|property|description|required?|
|--------|-----------|---------|
|dimName|The name of the spatial dimension. A spatial dimension may be constructed from multiple other dimensions or it may already exist as part of an event. If a spatial dimension already exists, it must be an array of coordinate values.|yes|
|dims|A list of dimension names that comprise a spatial dimension.|no|
The grammar for a spatial filter is as follows:
```json
"filter" : {
"type": "spatial",
"dimension": "spatialDim",
"bound": {
"type": "rectangular",
"minCoords": [10.0, 20.0],
"maxCoords": [30.0, 40.0]
}
}
```
### Bound types
#### `rectangular`
|property|description|required?|
|--------|-----------|---------|
|minCoords|List of minimum dimension coordinates for coordinates [x, y, z, …]|yes|
|maxCoords|List of maximum dimension coordinates for coordinates [x, y, z, …]|yes|
#### `radius`
|property|description|required?|
|--------|-----------|---------|
|coords|Origin coordinates in the form [x, y, z, …]|yes|
|radius|The float radius value|yes|
#### `polygon`
|property|description|required?|
|--------|-----------|---------|
|abscissa|Horizontal coordinate for corners of the polygon|yes|
|ordinate|Vertical coordinate for corners of the polygon|yes|