ST_MakeEnvelope — Creates a rectangular Polygon from minimum and maximum coordinates.
geometry ST_MakeEnvelope(float xmin, float ymin, float xmax, float ymax, integer srid=unknown);
Creates a rectangular Polygon from the minimum and maximum values for X and Y. Input values must be in the spatial reference system specified by the SRID. If no SRID is specified the unknown spatial reference system (SRID 0) is used.
Availability: 1.5
Enhanced: 2.0: Ability to specify an envelope without specifying an SRID was introduced.
Building a bounding box polygon.
SELECT ST_MakeEnvelope(10, 10, 11, 11, 4326);
POLYGON((10 10, 10 11, 11 11, 11 10, 10 10))