Categories:

Geospatial Functions, Conversion Functions

ST_GEOMETRYFROMWKT

Parses a WKT (well-known text) or EWKT (extended well-known text) input and returns a value of type GEOMETRY.

Aliases:

ST_GEOMFROMWKT , ST_GEOMETRYFROMEWKT , ST_GEOMFROMEWKT , ST_GEOMETRYFROMTEXT , ST_GEOMFROMTEXT

See also:

TO_GEOMETRY

Syntax

ST_GEOMETRYFROMWKT( <varchar_expression> )

ST_GEOMFROMWKT( <varchar_expression> )

ST_GEOMETRYFROMEWKT( <varchar_expression> )

ST_GEOMFROMEWKT( <varchar_expression> )

ST_GEOMETRYFROMTEXT( <varchar_expression> )

ST_GEOMFROMTEXT( <varchar_expression> )

Arguments

varchar_expression

The argument must be a string expression in WKT or EWKT that represents a valid geospatial object.

Returns

The function returns a value of type GEOMETRY.

Usage Notes

  • Issues an error if the input cannot be parsed as WKT or EWKT.

  • For WKT input, the resulting GEOMETRY object has SRID set to 0.

    To change the SRID of a GEOMETRY object, pass the GEOMETRY object to ST_SETSRID, specifying the SRID that you want to set. ST_SETSRID returns the GEOMETRY object that has the specified SRID.

Examples

The following example returns the GEOMETRY object for a geospatial object described in EWKT format:

-- Set the output format to EWKT
ALTER SESSION SET GEOMETRY_OUTPUT_FORMAT='EWKT';

SELECT ST_GEOMETRYFROMEWKT('SRID=32633;POINT(389866.35 5819003.03)');
+---------------------------------------------------------------+
| ST_GEOMETRYFROMEWKT('SRID=32633;POINT(389866.35 5819003.03)') |
|---------------------------------------------------------------|
| SRID=32633;POINT(389866.35 5819003.03)                        |
+---------------------------------------------------------------+

In the next example, the input is in WKT format, which does not specify the SRID:

-- Set the output format to WKT
ALTER SESSION SET GEOMETRY_OUTPUT_FORMAT='EWKT';

SELECT ST_GEOMETRYFROMWKT('POINT(389866.35 5819003.03)');
+----------------------------------------------------+
| ST_GEOMETRYFROMWKT('POINT(389866.35 5819003.03)')  |
|----------------------------------------------------|
| SRID=0;POINT(389866.35 5819003.03)                 |
+----------------------------------------------------+
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