feat(ingest): mssql - add type mappings for BIT and SQL_VARIANT (data…

…hub-project#6304)

metadata-ingestion/src/datahub/ingestion/source/sql/mssql.py

@@ -3,6 +3,7 @@
 from typing import Any, Dict, Iterable, List, Optional, Tuple
 
 import pydantic
+import sqlalchemy.dialects.mssql
 
 # This import verifies that the dependencies are available.
 import sqlalchemy_pytds  # noqa: F401
@@ -26,10 +27,15 @@
     BasicSQLAlchemyConfig,
     SQLAlchemySource,
     make_sqlalchemy_uri,
+    register_custom_type,
 )
+from datahub.metadata.schema_classes import BooleanTypeClass, UnionTypeClass
 
 logger: logging.Logger = logging.getLogger(__name__)
 
+register_custom_type(sqlalchemy.dialects.mssql.BIT, BooleanTypeClass)
+register_custom_type(sqlalchemy.dialects.mssql.SQL_VARIANT, UnionTypeClass)
+
 
 class SQLServerConfig(BasicSQLAlchemyConfig):
     # defaults