POLYGONFROMTEXT() — Returns a GEOGRAPHY value from the corresponding WKT
POLYGONFROMTEXT( text )
The POLYGONFROMTEXT() function generates a GEOGRAPHY value from a string containing a well known text (WKT) representation of a geographic polygon. The WKT string must be a valid representation of a polygon with only one outer polygon and, optionally, one or more inner polygons.
if the argument is not a valid WKT representation of a polygon, the function generates an error.