code: def add_sql_operation(self, app_label, sql_name, operation, dependencies):
          
          deps = [(dp[0], SQL_BLOB, dp[1], self._sql_operations.get(dp)) for dp in dependencies]
  
          self.add_operation(app_label, operation, dependencies=deps)
          self._sql_operations[(app_label, sql_name)] = operation
docs: Add SQL operation and register it to be used as dependency for further
          sequential operations.