Parse (geometry Data Type)
Applies to: 
SQL Server
Azure SQL Database
Azure SQL Managed Instance
Returns a geometry instance from an Open Geospatial Consortium (OGC) Well-Known Text (WKT) representation. Parse() is equivalent to STGeomFromText(), with the exception that it assumes a spatial reference ID (SRID) of 0 as a parameter. The input may carry optional Z (elevation) and M (measure) values.
Syntax
Parse ( 'geometry_tagged_text' )
Arguments
geometry_tagged_text
Is the WKT representation of the geometry instance you wish to return. geometry_tagged_text is an nvarchar expression.
Return Types
SQL Server return type: geometry
CLR return type: SqlGeometry
Remarks
The OGC type of the geometry instance returned by Parse() is set to the corresponding WKT input.
The string 'Null' will be interpreted as a null geometry instance.
This method will throw a FormatException if the input is not well-formatted.
Examples
The following example uses Parse() to create a geometry instance.
DECLARE @g geometry;
SET @g = geometry::Parse('LINESTRING (100 100, 20 180, 180 180)');
SELECT @g.ToString();