elasticsearch/docs/reference/query-languages/sql/sql-functions-geo.md

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---
mapped_pages:
- https://www.elastic.co/guide/en/elasticsearch/reference/current/sql-functions-geo.html
---
# Geo functions [sql-functions-geo]
::::{warning}
This functionality is in beta and is subject to change. The design and code is less mature than official GA features and is being provided as-is with no warranties. Beta features are not subject to the support SLA of official GA features.
::::
The geo functions work with geometries stored in `geo_point`, `geo_shape` and `shape` fields, or returned by other geo functions.
## Limitations [_limitations_4]
[`geo_point`](/reference/elasticsearch/mapping-reference/geo-point.md), [`geo_shape`](/reference/elasticsearch/mapping-reference/geo-shape.md) and [`shape`](/reference/elasticsearch/mapping-reference/shape.md) and types are represented in SQL as geometry and can be used interchangeably with the following exceptions:
* `geo_shape` and `shape` fields dont have doc values, therefore these fields cannot be used for filtering, grouping or sorting.
* `geo_points` fields are indexed and have doc values by default, however only latitude and longitude are stored and indexed with some loss of precision from the original values (4.190951585769653E-8 for the latitude and 8.381903171539307E-8 for longitude). The altitude component is accepted but not stored in doc values nor indexed. Therefore calling `ST_Z` function in the filtering, grouping or sorting will return `null`.
## Geometry Conversion [_geometry_conversion]
### `ST_AsWKT` [sql-functions-geo-st-as-wkt]
```sql
ST_AsWKT(
geometry <1>
)
```
**Input**:
1. geometry. If `null`, the function returns `null`.
**Output**: string
**Description**: Returns the WKT representation of the `geometry`.
```sql
SELECT city, ST_AsWKT(location) location FROM "geo" WHERE city = 'Amsterdam';
city:s | location:s
Amsterdam |POINT (4.850312 52.347557)
```
### `ST_WKTToSQL` [sql-functions-geo-st-wkt-to-sql]
```sql
ST_WKTToSQL(
string <1>
)
```
**Input**:
1. string WKT representation of geometry. If `null`, the function returns `null`.
**Output**: geometry
**Description**: Returns the geometry from WKT representation.
```sql
SELECT CAST(ST_WKTToSQL('POINT (10 20)') AS STRING) location;
location:s
POINT (10.0 20.0)
```
## Geometry Properties [_geometry_properties]
### `ST_GeometryType` [sql-functions-geo-st-geometrytype]
```sql
ST_GeometryType(
geometry <1>
)
```
**Input**:
1. geometry. If `null`, the function returns `null`.
**Output**: string
**Description**: Returns the type of the `geometry` such as POINT, MULTIPOINT, LINESTRING, MULTILINESTRING, POLYGON, MULTIPOLYGON, GEOMETRYCOLLECTION, ENVELOPE or CIRCLE.
```sql
SELECT ST_GeometryType(ST_WKTToSQL('POINT (10 20)')) type;
type:s
POINT
```
### `ST_X` [sql-functions-geo-st-x]
```sql
ST_X(
geometry <1>
)
```
**Input**:
1. geometry. If `null`, the function returns `null`.
**Output**: double
**Description**: Returns the longitude of the first point in the geometry.
```sql
SELECT ST_X(ST_WKTToSQL('POINT (10 20)')) x;
x:d
10.0
```
### `ST_Y` [sql-functions-geo-st-y]
```sql
ST_Y(
geometry <1>
)
```
**Input**:
1. geometry. If `null`, the function returns `null`.
**Output**: double
**Description**: Returns the latitude of the first point in the geometry.
```sql
SELECT ST_Y(ST_WKTToSQL('POINT (10 20)')) y;
y:d
20.0
```
### `ST_Z` [sql-functions-geo-st-z]
```sql
ST_Z(
geometry <1>
)
```
**Input**:
1. geometry. If `null`, the function returns `null`.
**Output**: double
**Description**: Returns the altitude of the first point in the geometry.
```sql
SELECT ST_Z(ST_WKTToSQL('POINT (10 20 30)')) z;
z:d
30.0
```
### `ST_Distance` [sql-functions-geo-st-distance]
```sql
ST_Distance(
geometry, <1>
geometry <2>
)
```
**Input**:
1. source geometry. If `null`, the function returns `null`.
2. target geometry. If `null`, the function returns `null`.
**Output**: Double
**Description**: Returns the distance between geometries in meters. Both geometries have to be points.
```sql
SELECT ST_Distance(ST_WKTToSQL('POINT (10 20)'), ST_WKTToSQL('POINT (20 30)')) distance;
distance:d
1499101.2889383635
```