ST_EnvelopeAsText

Signature

VARCHAR ST_EnvelopeAsText(GEOMETRY geom);

Description

Return a string representation of the envelope of geom : West, South, East, North → X_Min, Y_Min, X_Max, Y_Max.

Examples

With a `POINT`

SELECT ST_EnvelopeAsText('POINT(1 2)');
-- Answer: 1.0,2.0,1.0,2.0

With a `LINESTRING`

SELECT ST_EnvelopeAsText('LINESTRING(1 1, 5 5)');
-- Answer: 1.0,1.0,5.0,5.0

With a `LINESTRING` parallel to the x-axis

SELECT ST_EnvelopeAsText('LINESTRING(1 1, 5 1, 9 1)');
-- Answer: 1.0,1.0,9.0,1.0

With a `MULTIPOINT`

SELECT ST_EnvelopeAsText('MULTIPOINT(1 2, 3 1, 2 1, 5 1, 1 -1)');
-- Answer: 1.0,-1.0,5.0,2.0

With a `GEOMETRYCOLLECTION`

SELECT ST_EnvelopeAsText('GEOMETRYCOLLECTION(
                               MULTIPOINT(1 2, 2 1, 1 -1),
                               LINESTRING(3 -1, 5 1),
                               POLYGON((2 2, 4 3, 3 1, 2 2)))');
-- Answer: 1.0,-1.0,5.0,3.0

See also