docs/api/sql/Geometry-Output/ST_AsEWKT.md

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# ST_AsEWKT

Introduction: Return the Extended Well-Known Text representation of a geometry.
EWKT is an extended version of WKT which includes the SRID of the geometry.
The format originated in PostGIS but is supported by many GIS tools.
If the geometry is lacking SRID a WKT format is produced.
[See ST_SetSRID](../Spatial-Reference-System/ST_SetSRID.md)
It will support M coordinate if present since v1.5.0.

Format: `ST_AsEWKT (A: Geometry)`

Return type: `String`

Since: `v1.2.1`

SQL Example

```sql
SELECT ST_AsEWKT(ST_SetSrid(ST_GeomFromWKT('POLYGON((0 0,0 1,1 1,1 0,0 0))'), 4326))
```

Output:

```
SRID=4326;POLYGON ((0 0, 0 1, 1 1, 1 0, 0 0))
```

SQL Example

```sql
SELECT ST_AsEWKT(ST_MakePointM(1.0, 1.0, 1.0))
```

Output:

```
POINT M(1 1 1)
```

SQL Example

```sql
SELECT ST_AsEWKT(ST_MakePoint(1.0, 1.0, 1.0, 1.0))
```

Output:

```
POINT ZM(1 1 1 1)
```