Removed superfluous code now that connections use autocommit by default.

django/db/backends/creation.py

@@ -383,10 +383,7 @@ class BaseDatabaseCreation(object):
 
         qn = self.connection.ops.quote_name
 
-        # Create the test database and connect to it. We need to autocommit
-        # if the database supports it because PostgreSQL doesn't allow
-        # CREATE/DROP DATABASE statements within transactions.
-        self._prepare_for_test_db_ddl()
+        # Create the test database and connect to it.
         cursor = self.connection.cursor()
         try:
             cursor.execute(
@@ -454,7 +451,6 @@ class BaseDatabaseCreation(object):
         # to do so, because it's not allowed to delete a database while being
         # connected to it.
         cursor = self.connection.cursor()
-        self._prepare_for_test_db_ddl()
         # Wait to avoid "database is being accessed by other users" errors.
         time.sleep(1)
         cursor.execute("DROP DATABASE %s"
@@ -472,15 +468,6 @@ class BaseDatabaseCreation(object):
             "BaseDatabaseWrapper.", PendingDeprecationWarning, stacklevel=2)
         return self.connection.set_autocommit()
 
-    def _prepare_for_test_db_ddl(self):
-        """
-        Internal implementation - Hook for tasks that should be performed
-        before the ``CREATE DATABASE``/``DROP DATABASE`` clauses used by
-        testing code to create/ destroy test databases. Needed e.g. in
-        PostgreSQL to rollback and close any active transaction.
-        """
-        pass
-
     def sql_table_creation_suffix(self):
         """
         SQL to append to the end of the test table creation statements.

django/db/backends/postgresql_psycopg2/creation.py

@@ -77,11 +77,3 @@ class DatabaseCreation(BaseDatabaseCreation):
                 output.append(get_index_sql('%s_%s_like' % (db_table, f.column),
                                             ' text_pattern_ops'))
         return output
-
-    def _prepare_for_test_db_ddl(self):
-        """Rollback and close the active transaction."""
-        # Make sure there is an open connection.
-        self.connection.cursor()
-        self.connection.connection.rollback()
-        self.connection.connection.set_isolation_level(
-                psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT)