Use ST_Within to query if a geometry is within another - PolarDB

ST_Within queries whether a grid is contained in a geometry. It accepts geomgrid and geometry arguments and returns a boolean.

Syntax

boolean ST_Within(geomgrid grid, geometry geom);
boolean ST_Within(geometry geom, geomgrid grid);
boolean ST_Within(geomgrid grid1, geomgrid grid2);

Parameters

Parameter	Description
`grid`	The grid whose spatial relationship you want to query.
`geom`	The geometry whose spatial relationship you want to query.

Description

ST_Within returns the spatial relationship between a grid and a geometry. The geometry argument must use the CGC2000 spatial reference system. Its spatial reference system identifier (SRID) must be 4490.

Examples

Example 1: Test whether a point is within a grid

The point lies outside the grid, so the function returns f.

SELECT ST_Within(
  ST_geomfromtext('POINT(116.31522216796875 39.910277777777778)', 4490),
  ST_gridfromtext('G001331032213300013')
);

 st_within
-----------
 f

Example 2: Test whether a smaller grid is within a larger grid

SELECT ST_Within(
  ST_gridfromtext('G001331032213300013'),
  ST_gridfromtext('G001331032213300')
);

 st_within
-----------
 t