STEquals (geography Data Type)
Applies to: 
SQL Server
Azure SQL Database
Azure SQL Managed Instance
SQL database in Microsoft Fabric
Returns 1 if a geography instance represents the same point set as another geography instance. Returns 0 if it does not.
.STEquals ( other_geography )
other_geography
Is another geography instance to compare against the instance on which STEquals() is invoked.
SQL Server return type: bit
CLR return type: SqlBoolean
This method always returns null if the spatial reference IDs (SRIDs) of the geography instances do not match.
The following example creates two geography instances with STGeomFromText() that are equal but not trivially equal, and uses STEquals() to test their equality. The instances are equal because LINESTRING and POINT are contained within the POLYGON.
DECLARE @g geography;
DECLARE @h geography;
SET @g = geography::STGeomFromText('GEOMETRYCOLLECTION(POLYGON((-122.368 47.658, -122.338 47.649, -122.338 47.658, -122.368 47.658, -122.368 47.658)), LINESTRING(-122.360 47.656, -122.343 47.656), POINT (-122.35 47.656))', 4326);
SET @h = geography::STGeomFromText('POLYGON((-122.368 47.658, -122.338 47.649, -122.338 47.658, -122.368 47.658, -122.368 47.658))', 4326);
SELECT @g.STEquals(@h);