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| |
| # ST_IsValid |
| |
| Introduction: Test if a geometry is well-formed. The function can be invoked with just the geometry or with an additional flag (from `v1.5.1`). The flag alters the validity checking behavior. The flags parameter is a bitfield with the following options: |
| |
| - 0 (default): Use usual OGC SFS (Simple Features Specification) validity semantics. |
| - 1: "ESRI flag", Accepts certain self-touching rings as valid, which are considered invalid under OGC standards. |
| |
|  |
| |
| Formats: |
| |
| ``` |
| ST_IsValid (A: Geometry) |
| ``` |
| |
| ``` |
| ST_IsValid (A: Geometry, flag: Integer) |
| ``` |
| |
| Return type: `Boolean` |
| |
| Since: `v1.0.0` |
| |
| SQL Example: |
| |
| ```sql |
| SELECT ST_IsValid(ST_GeomFromWKT('POLYGON((0 0, 10 0, 10 10, 0 10, 0 0), (15 15, 15 20, 20 20, 20 15, 15 15))')) |
| ``` |
| |
| Output: |
| |
| ``` |
| false |
| ``` |
