This topic describes the ST_MakeValid function. This function converts an invalid input geometry object into a valid geometry object without deleting vertexes.
Syntax
geometry ST_MakeValid(geometry input);Parameters
Parameter | Description |
input | The geometry object that you want to specify. |
Description
This function processes only invalid geometry objects.
This function supports point objects, MultiPoint objects, LineString objects, MultiLineString objects, polygon objects, MultiPolygon objects, and GeometryCollection objects. The combination of the preceding objects is also supported.
If all or partial dimensions of the input geometry object are missing, this function returns a geometry object from lower dimensions or a collection of geometry objects from lower dimensions.
If you specify a polygon object that has self-intersections, this function may return a MULTI object.
Examples
Results returned by specifying a polygon object with self-intersections:
st_astext
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MULTIPOLYGON(((0.5 0.5,0 0,0 1,0.5 0.5)),((1 0,0.5 0.5,1 1,1 0)))
(1 row)