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| |
| # ST_UnaryUnion |
| |
| Introduction: This variant of [ST_Union](ST_Union.md) operates on a single geometry input. The input geometry can be a simple Geometry type, a MultiGeometry, or a GeometryCollection. The function calculates the geometric union across all components and elements within the provided geometry object. |
| |
|  |
| |
| Format: `ST_UnaryUnion(geometry: Geometry)` |
| |
| Return type: `Geometry` |
| |
| Since: `v1.6.1` |
| |
| SQL Example |
| |
| ```sql |
| SELECT ST_UnaryUnion(ST_GeomFromWKT('MULTIPOLYGON(((0 10,0 30,20 30,20 10,0 10)),((10 0,10 20,30 20,30 0,10 0)))')) |
| ``` |
| |
| Output: |
| |
| ``` |
| POLYGON ((10 0, 10 10, 0 10, 0 30, 20 30, 20 20, 30 20, 30 0, 10 0)) |
| ``` |
