Tests if an ST_Geometry type that represents an ST_LineString, GeoSequence, or ST_MultiLineString value is closed.
Returns an INTEGER value.
ST_LineString, GeoSequence, and ST_MultiLineString
An ST_LineString value is closed if the start point of the ST_LineString value is equal to the end point.
WHERE shape.ST_IsClosed() = 0
ORDER BY skey;