druid/docs/querying/geo.md

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---
id: geo
title: "Spatial filters"
---
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:::info
Apache Druid supports two query languages: [Druid SQL](../querying/sql.md) and [native queries](../querying/querying.md).
This document describes a feature that is only available in the native language.
:::
Apache Druid supports filtering spatially indexed columns based on an origin and a bound.
This topic explains how to ingest and query spatial filters.
For information on other filters supported by Druid, see [Query filters](../querying/filters.md).
## Spatial indexing
Spatial indexing refers to ingesting data of a spatial data type, such as geometry or geography, into Druid.
Spatial dimensions are string columns that contain coordinates separated by a comma.
In the ingestion spec, you configure spatial dimensions in the `dimensionsSpec` object of the `dataSchema` component.
You can provide spatial dimensions in any of the [data formats](../ingestion/data-formats.md) supported by Druid.
The following example shows an ingestion spec with a spatial dimension named `coordinates`, which is constructed from the input fields `x` and `y`:
```json
{
"type": "hadoop",
"dataSchema": {
"dataSource": "DatasourceName",
"parser": {
"type": "string",
"parseSpec": {
"format": "json",
"timestampSpec": {
"column": "timestamp",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [
{
"type": "double",
"name": "x"
},
{
"type": "double",
"name": "y"
}
],
"spatialDimensions": [
{
"dimName": "coordinates",
"dims": [
"x",
"y"
]
}
]
}
}
}
}
}
```
Each spatial dimension object in the `spatialDimensions` array is defined by the following fields:
|Property|Description|Required|
|--------|-----------|--------|
|`dimName`|The name of a spatial dimension. You can construct a spatial dimension from 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`|The list of dimension names that comprise the spatial dimension.|no|
For information on how to use the ingestion spec to configure ingestion, see [Ingestion spec reference](../ingestion/ingestion-spec.md).
For general information on loading data in Druid, see [Ingestion](../ingestion/index.md).
## Spatial filters
A [filter](../querying/filters.md) is a JSON object indicating which rows of data should be included in the computation for a query.
You can filter on spatial structures, such as rectangles and polygons, using the spatial filter.
Spatial filters have the following structure:
```json
"filter": {
"type": "spatial",
"dimension": <name_of_spatial_dimension>,
"bound": <bound_type>
}
```
The following example shows a spatial filter with a rectangular bound type:
```json
"filter" : {
"type": "spatial",
"dimension": "spatialDim",
"bound": {
"type": "rectangular",
"minCoords": [10.0, 20.0],
"maxCoords": [30.0, 40.0]
}
```
The order of the dimension coordinates in the spatial filter must be equal to the order of the dimension coordinates in the `spatialDimensions` array.
### Bound types
The `bound` property of the spatial filter object lets you filter on ranges of dimension values.
You can define rectangular, radius, and polygon filter bounds.
#### Rectangular
The `rectangular` bound has the following elements:
|Property|Description|Required|
|--------|-----------|--------|
|`minCoords`|The list of minimum dimension coordinates in the form [x, y]|yes|
|`maxCoords`|The list of maximum dimension coordinates in the form [x, y]|yes|
#### Radius
The `radius` bound has the following elements:
|Property|Description|Required|
|--------|-----------|--------|
|`coords`|Origin coordinates in the form [x, y]|yes|
|`radius`|The float radius value|yes|
#### Polygon
The `polygon` bound has the following elements:
|Property|Description|Required|
|--------|-----------|--------|
|`abscissa`|Horizontal coordinates for the corners of the polygon|yes|
|`ordinate`|Vertical coordinates for the corners of the polygon|yes|