Categories:

Geospatial Functions, Conversion Functions

ST_GEOGRAPHYFROMWKT

Parses a WKT or EWKT input and returns a value of type GEOGRAPHY.

Aliases:

ST_GEOGFROMWKT , ST_GEOGRAPHYFROMEWKT , ST_GEOGFROMEWKT , ST_GEOGRAPHYFROMTEXT , ST_GEOGFROMTEXT

See also:

TO_GEOGRAPHY

Syntax

ST_GEOGRAPHYFROMWKT( <varchar_expression> )

ST_GEOGFROMWKT( <varchar_expression> )

ST_GEOGRAPHYFROMEWKT( <varchar_expression> )

ST_GEOGFROMEWKT( <varchar_expression> )

ST_GEOGRAPHYFROMTEXT( <varchar_expression> )

ST_GEOGFROMTEXT( <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 GEOGRAPHY.

Usage Notes

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

  • Issues an error if the input format is EWKT and the SRID is not 4326. See the note on EWKT and EWKB handling.

  • For the coordinates in WKT and EWKT, longitude appears before latitude (e.g. POINT(lon, lat)).

Examples

The following example returns the GEOGRAPHY object for a geospatial object described in WKT format:

-- Set the output format to WKT
alter session set GEOGRAPHY_OUTPUT_FORMAT='WKT';
select ST_GEOGRAPHYFROMWKT('POINT(-122.35 37.55)');
+---------------------------------------------+
| ST_GEOGRAPHYFROMWKT('POINT(-122.35 37.55)') |
|---------------------------------------------|
| POINT(-122.35 37.55)                        |
+---------------------------------------------+

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

-- Set the output format to EWKT
alter session set GEOGRAPHY_OUTPUT_FORMAT='EWKT';
select ST_GEOGRAPHYFROMEWKT('SRID=4326;POINT(-122.35 37.55)');
+--------------------------------------------------------+
| ST_GEOGRAPHYFROMEWKT('SRID=4326;POINT(-122.35 37.55)') |
|--------------------------------------------------------|
| SRID=4326;POINT(-122.35 37.55)                         |
+--------------------------------------------------------+