STRelate (geometry Data Type)
Applies to: 
SQL Server
Azure SQL Database
Azure SQL Managed Instance
Returns 1 if a geometry instance is related to another geometry instance, where the relationship is defined by a Dimensionally Extended 9 Intersection Model (DE-9IM) pattern matrix value; otherwise, returns 0.
Syntax
.STRelate ( other_geometry, intersection_pattern_matrix )
Arguments
other_geometry
Is another geometry instance to compare against the instance on which STRelate() is invoked.
intersection_pattern_matrix
Is a string of type nchar(9) encoding acceptable values for the DE-9IM pattern matrix device between the two geometry instances.
Remarks
This method always returns null if the spatial reference IDs (SRIDs) of the geometry instances do not match. This method will throw an ArgumentException if the matrix isn't well formed.
Return Types
SQL Server return type: bit
CLR return type: SqlBoolean
Examples
The following example uses STRelate() to test two geometry instances for spatial disjoint using an explicit DE-9IM pattern.
DECLARE @g geometry;
DECLARE @h geometry;
SET @g = geometry::STGeomFromText('LINESTRING(0 2, 2 0, 4 2)', 0);
SET @h = geometry::STGeomFromText('POINT(5 5)', 0);
SELECT @g.STRelate(@h, 'FF*FF****');