Checks whether a spatial object is empty.
Syntax
boolean ST_IsEmpty(meshgeom geom);
boolean ST_IsEmpty(sfmesh sfmeshObject);Parameters
| Parameter | Type | Description |
|---|---|---|
geom | meshgeom | The meshgeom object to check. |
sfmeshObject | sfmesh | The sfmesh object to check. |
Return value
Returns t (true) if the object is empty, or f (false) if the object is not empty.
Examples
Check a meshgeom object that contains geometry data:
SELECT ST_IsEmpty('MESHGEOM(PATCH(INDEXSURFACE(VERTEX(0 0 2,0 10 3,10 10 1,10 0 1), INDEX((0,1,2),(1,2,3)))))'::meshgeom);Result:
fCheck an empty meshgeom object:
SELECT ST_IsEmpty('MESHGEOM EMPTY'::meshgeom);Result:
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