15.10 - ST_ExteriorRing - Teradata Database

Teradata Database SQL Geospatial Types

Teradata Database
Programming Reference

Get and set the exterior ring of an ST_Geometry type that represents an ST_Polygon value.


Argument …

Specifies …


an ST_Geometry type that represents an ST_LineString for the new exterior ring of the polygon.

Returns an ST_Geometry value.


IF you …

THEN ST_ExteriorRing returns …

do not pass in the acurve argument

an ST_LineString of the exterior ring of the ST_Polygon.

pass in the acurve argument

the new ST_Polygon with the exterior ring set to the value of the acurve argument.


Note: This method can be called on 3D geometries (those that include z coordinates). However, the z coordinate is ignored in method calculations. Consequently, any z coordinates returned by this method should be ignored. Teradata recommends using the Make_2D method to strip out the z coordinates of the return value.

ST_ExteriorRing returns an error if the geometry value passed to it is the empty set.

   SELECT cityName, cityShape.ST_ExteriorRing()
   FROM sample_cities
   WHERE skey = 1044;