This topic describes the ST_GeometryN function. This function returns the Nth geometry of an input geometry.
Syntax
meshgeom ST_NumGeometries(meshgeom geom, integer index );
meshgeom ST_NumGeometries(sfmesh sfmeshObject, integer index );Parameters
| Parameter | Description |
|---|---|
| geom | The meshgeom object. |
| sfmeshObject | The sfmesh object. |
| index | The sequence number of the geometry that you want to obtain. The value of this parameter starts from 0. |
Description
The function returns the Nth geometry of an input geometry.
Examples
select ST_AsText(ST_GeometryN('MESHGEOM(PATCH(INDEXSURFACE(VERTEX(0 0 2,0 10 3,10 10 1,10 0 1), INDEX((0,1,2),(1,2,3)))))'::meshgeom, 0));
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MESHGEOM(PATCH(INDEXSURFACE Z (VERTEX(0 0 2,0 10 3,10 10 1,10 0 1),INDEX((0,1,2),(1,2,3)))))