Product Documentation

Appearance

All platforms

ST_ENVELOPE ​

Returns a double-precision minimum bounding box for the supplied geography. The polygon is defined by the corner points ((MINX, MINY), (MINX, MAXY), (MAXX, MAXY), (MAXX, MINY), (MINX, MINY)).

For degenerate cases (e.g.: vertical lines or points), returns a GEOGRAPHY of a lower dimension (POINT or LINESTRING).

Syntax ​

sql
ST_ENVELOPE(<input>)

Arguments ​

  • <input>: A GEOGRAPHY object to calculate the envelope

Returns ​

A GEOGRAPHY representing the bounding box. Return type depends on input:

  • For most cases: returns a POLYGON defined by the corner points
  • For vertical lines or horizontal lines: returns a LINESTRING
  • For points: returns a POINT

Example ​

sql
SELECT ST_AsText(ST_Envelope('LINESTRING(0 0, 1 1, 2 2)'::GEOGRAPHY));
-- POLYGON((0 0, 0 2, 2 2, 2 0, 0 0))

SELECT ST_AsText(ST_Envelope('POINT(1 1)'::GEOGRAPHY));
-- POINT(1 1)