PostGIS
Name
ST_AsText — Return the Well-Known Text (WKT) representation of the geometry/geography without SRID metadata.
Synopsis
+text +ST_AsText(+`geometry `+g1`)`;
+text +ST_AsText(+`geometry `+g1, integer
maxdecimaldigits = 15`)`;
+text +ST_AsText(+`geography `+g1`)`;
+text +ST_AsText(+`geography `+g1, integer
maxdecimaldigits = 15`)`;
Description
Returns the OGC Well-Known Text (WKT) representation of the geometry/geography. The optional `maxdecimaldigits` argument may be used to limit the number of digits after the decimal point in output ordinates (defaults to 15).
To perform the inverse conversion of WKT representation to PostGIS geometry use ST_GeomFromText.
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Availability: 1.5 - support for geography was introduced.
Enhanced: 2.5 - optional parameter precision introduced.
This method
implements the OGC Simple
Features Implementation Specification for SQL 1.1. s2.1.1.1
This method
implements the SQL/MM specification. SQL-MM 3: 5.1.25
This method
supports Circular Strings and Curves
Examples
SELECT ST_AsText('01030000000100000005000000000000000000
000000000000000000000000000000000000000000000000
F03F000000000000F03F000000000000F03F000000000000F03
F000000000000000000000000000000000000000000000000');
st_astext
--------------------------------
POLYGON((0 0,0 1,1 1,1 0,0 0))Full precision output is the default.
SELECT ST_AsText('POINT(111.1111111 1.1111111)'));
st_astext
------------------------------
POINT(111.1111111 1.1111111)The `maxdecimaldigits` argument can be used to limit output precision.
SELECT ST_AsText('POINT(111.1111111 1.1111111)'), 2);
st_astext
--------------------
POINT(111.11 1.11)