docs: def if_sqlserver_disable_constraints(session: SqlASession,
                                       tablename: str) -> None:
      """
      If we're running under SQL Server, disable constraint checking for the
      specified table while the resource is held.
  
      Args:
          session: SQLAlchemy :class:`Session`
          tablename: table name
  
      See
      https://stackoverflow.com/questions/123558/sql-server-2005-t-sql-to-temporarily-disable-a-trigger
      """  # noqa
      engine = get_engine_from_session(session)
      if is_sqlserver(engine):
          quoted_tablename = quote_identifier(tablename, engine)
          session.execute(
              "ALTER TABLE {} NOCHECK CONSTRAINT all".format(
                  quoted_tablename))
          yield
          session.execute(
              "ALTER TABLE {} WITH CHECK CHECK CONSTRAINT all".format(
                  quoted_tablename))
      else:
          yield