ST_MakeEnvelope - Amazon Redshift

ST_MakeEnvelope

ST_MakeEnvelope returns a geometry as follows:

  • If the input coordinates specify a point, then the returned geometry is a point.

  • If the input coordinates specify a line, then the returned geometry is a linestring.

  • Otherwise, the returned geometry is a polygon, where the input coordinates specify the lower-left and upper-right corners of a box.

If provided, the spatial reference system identifier (SRID) value of the returned geometry is set to the input SRID value.

Syntax

ST_MakeEnvelope(xmin, ymin, xmax, ymax)
ST_MakeEnvelope(xmin, ymin, xmax, ymax, srid)

Arguments

xmin

A value of data type DOUBLE PRECISION. This value is the first coordinate of the lower-left corner of a box.

ymin

A value of data type DOUBLE PRECISION. This value is the second coordinate of the lower-left corner of a box.

xmax

A value of data type DOUBLE PRECISION. This value is the first coordinate of the upper-right corner of a box.

ymax

A value of data type DOUBLE PRECISION. This value is the second coordinate of the upper-right corner of a box.

srid

A value of data type INTEGER that represents a spatial reference system identifier (SRID). If the SRID value is not provided, then it is set to zero.

Return type

GEOMETRY of subtype POINT, LINESTRING, or POLYGON.

The SRID of the returned geometry is set to srid or zero if srid isn't set.

If xmin, ymin, xmax, ymax, or srid is null, then null is returned.

If srid is negative, then an error is returned.

Examples

The following SQL returns a polygon representing an envelope defined by the four input coordinate values.

SELECT ST_AsEWKT(ST_MakeEnvelope(2,4,5,7));
st_astext --------------- POLYGON((2 4,2 7,5 7,5 4,2 4))

The following SQL returns a polygon representing an envelope defined by the four input coordinate values and an SRID value.

SELECT ST_AsEWKT(ST_MakeEnvelope(2,4,5,7,4326));
st_astext ---------------------------------- SRID=4326;POLYGON((2 4,2 7,5 7,5 4,2 4))