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ApsaraDB RDS:ST_HasZ

Last Updated:Mar 28, 2026

Returns true if a geographic grid object (geomgrid) has a Z dimension, or false if it does not. Grids with a Z dimension carry elevation or height data and represent 3D spatial positions; those without represent 2D positions only.

Syntax

bool ST_HasZ(geomgrid gridcode);

Parameters

ParameterDescription
gridcodeThe geographic grid object to check.

Examples

The following example checks whether the grid GZ0026206440 contains a Z dimension. The output t (true) indicates that it does.

SELECT ST_HasZ(ST_GridFromText('GZ0026206440'));

Output:

 st_hasz
---------
 t