opensearch-docs-cn/_query-dsl/aggregations/bucket/geotile-grid.md

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---
layout: default
title: Geotile grid
parent: Bucket aggregations
grand_parent: Aggregations
nav_order: 87
---
# Geotile grid aggregations
The geotile grid aggregation groups [geopoints]({{site.url}}{{site.baseurl}}/opensearch/supported-field-types/geo-point/) into grid cells for geographical analysis. Each grid cell corresponds to a [map tile](https://en.wikipedia.org/wiki/Tiled_web_map) and is identified using the `{zoom}/{x}/{y}` format.
## Precision
The `precision` parameter controls the level of granularity that determines the grid cell size. The lower the precision, the larger the grid cells.
The following example illustrates low-precision and high-precision aggregation requests.
To start, create an index and map the `location` field as a `geo_point`:
```json
PUT national_parks
{
"mappings": {
"properties": {
"location": {
"type": "geo_point"
}
}
}
}
```
{% include copy-curl.html %}
Index the following documents into the sample index:
```json
PUT national_parks/_doc/1
{
"name": "Yellowstone National Park",
"location": "44.42, -110.59"
}
```
{% include copy-curl.html %}
```json
PUT national_parks/_doc/2
{
"name": "Yosemite National Park",
"location": "37.87, -119.53"
}
```
{% include copy-curl.html %}
```json
PUT national_parks/_doc/3
{
"name": "Death Valley National Park",
"location": "36.53, -116.93"
}
```
{% include copy-curl.html %}
You can index geopoints in several formats. For a list of all supported formats, see the [geopoint documentation]({{site.url}}{{site.baseurl}}/opensearch/supported-field-types/geo-point#formats).
{: .note}
## Low-precision requests
Run a low-precision request that buckets all three documents together:
```json
GET national_parks/_search
{
"aggregations": {
"grouped": {
"geotile_grid": {
"field": "location",
"precision": 1
}
}
}
}
```
{% include copy-curl.html %}
You can use either the `GET` or `POST` HTTP method for geotile grid aggregation queries.
{: .note}
The response groups all documents together because they are close enough to be bucketed in one grid cell:
```json
{
"took": 51,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 3,
"relation": "eq"
},
"max_score": 1,
"hits": [
{
"_index": "national_parks",
"_id": "1",
"_score": 1,
"_source": {
"name": "Yellowstone National Park",
"location": "44.42, -110.59"
}
},
{
"_index": "national_parks",
"_id": "2",
"_score": 1,
"_source": {
"name": "Yosemite National Park",
"location": "37.87, -119.53"
}
},
{
"_index": "national_parks",
"_id": "3",
"_score": 1,
"_source": {
"name": "Death Valley National Park",
"location": "36.53, -116.93"
}
}
]
},
"aggregations": {
"grouped": {
"buckets": [
{
"key": "1/0/0",
"doc_count": 3
}
]
}
}
}
```
## High-precision requests
Now run a high-precision request:
```json
GET national_parks/_search
{
"aggregations": {
"grouped": {
"geotile_grid": {
"field": "location",
"precision": 6
}
}
}
}
```
{% include copy-curl.html %}
All three documents are bucketed separately because of higher granularity:
```json
{
"took": 15,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 3,
"relation": "eq"
},
"max_score": 1,
"hits": [
{
"_index": "national_parks",
"_id": "1",
"_score": 1,
"_source": {
"name": "Yellowstone National Park",
"location": "44.42, -110.59"
}
},
{
"_index": "national_parks",
"_id": "2",
"_score": 1,
"_source": {
"name": "Yosemite National Park",
"location": "37.87, -119.53"
}
},
{
"_index": "national_parks",
"_id": "3",
"_score": 1,
"_source": {
"name": "Death Valley National Park",
"location": "36.53, -116.93"
}
}
]
},
"aggregations": {
"grouped": {
"buckets": [
{
"key": "6/12/23",
"doc_count": 1
},
{
"key": "6/11/25",
"doc_count": 1
},
{
"key": "6/10/24",
"doc_count": 1
}
]
}
}
}
```
You can also restrict the geographical area by providing the coordinates of the bounding envelope in the `bounds` parameter. Both `bounds` and `geo_bounding_box` coordinates can be specified in any of the [geopoint formats]({{site.url}}{{site.baseurl}}/opensearch/supported-field-types/geo-point#formats). The following query uses the well-known text (WKT) "POINT(`longitude` `latitude`)" format for the `bounds` parameter:
```json
GET national_parks/_search
{
"size": 0,
"aggregations": {
"grouped": {
"geotile_grid": {
"field": "location",
"precision": 6,
"bounds": {
"top_left": "POINT (-120 38)",
"bottom_right": "POINT (-116 36)"
}
}
}
}
}
```
{% include copy-curl.html %}
The response contains only the two results that are within the specified bounds:
```json
{
"took": 48,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 3,
"relation": "eq"
},
"max_score": 1,
"hits": [
{
"_index": "national_parks",
"_id": "1",
"_score": 1,
"_source": {
"name": "Yellowstone National Park",
"location": "44.42, -110.59"
}
},
{
"_index": "national_parks",
"_id": "2",
"_score": 1,
"_source": {
"name": "Yosemite National Park",
"location": "37.87, -119.53"
}
},
{
"_index": "national_parks",
"_id": "3",
"_score": 1,
"_source": {
"name": "Death Valley National Park",
"location": "36.53, -116.93"
}
}
]
},
"aggregations": {
"grouped": {
"buckets": [
{
"key": "6/11/25",
"doc_count": 1
},
{
"key": "6/10/24",
"doc_count": 1
}
]
}
}
}
```
The `bounds` parameter can be used with or without the `geo_bounding_box` filter; these two parameters are independent and can have any spatial relationship to each other.
## Supported parameters
Geotile grid aggregation requests support the following parameters.
Parameter | Data type | Description
:--- | :--- | :---
field | String | The field that contains the geopoints. This field must be mapped as a `geo_point` field. If the field contains an array, all array values are aggregated. Required.
precision | Integer | The zoom level used to determine grid cells for bucketing results. Valid values are in the [0, 15] range. Optional. Default is 5.
bounds | Object | The bounding box for filtering geopoints. The bounding box is defined by the upper-left and lower-right vertices. The vertices are specified as geopoints in one of the following formats: <br>- An object with a latitude and longitude<br>- An array in the [`longitude`, `latitude`] format<br>- A string in the "`latitude`,`longitude`" format<br>- A geohash <br>- WKT<br> See the [geopoint formats]({{site.url}}{{site.baseurl}}/opensearch/supported-field-types/geo-point#formats) for formatting examples. Optional.
size | Integer | The maximum number of buckets to return. When there are more buckets than `size`, OpenSearch returns buckets with more documents. Optional. Default is 10,000.
shard_size | Integer | The maximum number of buckets to return from each shard. Optional. Default is max (10, `size` &middot; number of shards), which provides a more accurate count of more highly prioritized buckets.