17.05 - Usage Notes - Teradata Database
Teradata Vantage™ - Geospatial Data Types
- Advanced SQL Engine
- Teradata Database
- June 2020
- Programming Reference
- The ST_IsValid method can be used to validate converted 2D geometries that were not validated by Make_2D.
- If the input geometry is already a 2D geometry value, this value is returned unchanged by this method.
- A well-formed 3D geometry value can become invalid during a 3D to 2D conversion. For example, if a 3D polygon lies in a plane parallel to the y axis, its line segments will self-intersect. Make_2D does not attempt to change the geometry type of the converted geometry from polygon to linestring to account for this, and an invalid 2D geometry can result.