Disable all constraints when dropping table

Author: OskarPersson

sql_server/pyodbc/base.py

@@ -480,18 +480,11 @@ def check_constraints(self, table_names=None):
                               table_names)
 
     def disable_constraint_checking(self):
-        # Azure SQL Database doesn't support sp_msforeachtable
-        # cursor.execute('EXEC sp_msforeachtable "ALTER TABLE ? NOCHECK CONSTRAINT ALL"')
-        if not self.needs_rollback:
-            self._execute_foreach('ALTER TABLE %s NOCHECK CONSTRAINT ALL')
-        return not self.needs_rollback
+        self.cursor().execute('EXEC sp_msforeachtable "ALTER TABLE ? NOCHECK CONSTRAINT ALL"')
+        return True
 
     def enable_constraint_checking(self):
-        # Azure SQL Database doesn't support sp_msforeachtable
-        # cursor.execute('EXEC sp_msforeachtable "ALTER TABLE ? WITH CHECK CHECK CONSTRAINT ALL"')
-        if not self.needs_rollback:
-            self.check_constraints()
-
+        self.cursor().execute('EXEC sp_msforeachtable "ALTER TABLE ? WITH CHECK CHECK CONSTRAINT ALL"')
 
 class CursorWrapper(object):
     """

sql_server/pyodbc/schema.py

@@ -330,16 +330,14 @@ def _alter_field(self, model, old_field, new_field, old_type, new_type,
             for constraint_name in constraint_names:
                 self.execute(self._delete_constraint_sql(self.sql_delete_check, model, constraint_name))
         # Have they renamed the column?
-        old_create_indexes_sql = []
         if old_field.column != new_field.column:
             # remove old indices
-            old_create_indexes_sql = self._model_indexes_sql(model)
             self._delete_indexes(model, old_field, new_field)
 
             self.execute(self._rename_field_sql(model._meta.db_table, old_field, new_field, new_type))
             # Rename all references to the renamed column.
             for sql in self.deferred_sql:
-                if isinstance(sql, Statement):
+                if isinstance(sql, DjStatement):
                     sql.rename_column_references(model._meta.db_table, old_field.column, new_field.column)
 
         # Next, start accumulating actions to do
@@ -553,13 +551,6 @@ def _alter_field(self, model, old_field, new_field, old_type, new_type,
             }
             self.execute(sql, params)
 
-        for o in old_create_indexes_sql:
-            o = str(o)
-            if old_field.column not in o:
-                continue
-            o = o.replace('[%s]' % old_field.column, '[%s]' % new_field.column)
-            self.execute(o)
-
         # Reset connection if required
         if self.connection.features.connection_persists_old_columns:
             self.connection.close()
@@ -587,11 +578,6 @@ def _delete_unique_constraints(self, model, old_field, new_field, strict=False):
         unique_columns = []
         if old_field.unique and new_field.unique:
             unique_columns.append([old_field.column])
-        else:
-            for fields in model._meta.unique_together:
-                columns = [model._meta.get_field(field).column for field in fields]
-                if old_field.column in columns:
-                    unique_columns.append(columns)
         if unique_columns:
             for columns in unique_columns:
                 constraint_names = self._constraint_names(model, columns, unique=True)