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| |
| # ST_Intersection |
| |
| Introduction: Return the intersection geometry of A and B |
| |
|  |
| |
| Format: `ST_Intersection (A:geometry, B:geometry)` |
| |
| Return type: `Geometry` |
| |
| !!!note |
| If you encounter a `TopologyException` with the message "found non-noded intersection", this is a known issue with the legacy overlay implementation in JTS. The OverlayNG algorithm resolves this. To enable it, add the following JVM flag: |
| |
| ``` |
| -Djts.overlay=ng |
| ``` |
| |
| SQL example: |
| |
| ```sql |
| SELECT ST_Intersection(polygondf.countyshape, polygondf.countyshape) |
| FROM polygondf |
| ``` |
