Fixed #31473 -- Made sql_flush() use RESTART IDENTITY to reset sequences on PostgreSQL.

The sql_flush() positional argument sequences is replaced by the boolean
keyword-only argument reset_sequences. This ensures that the old
function signature can't be used by mistake when upgrading Django. When
the new argument is True, the sequences of the truncated tables will
reset. Using a single boolean value, rather than a list, allows making a
binary yes/no choice as to whether to reset all sequences rather than a
working on a completely different set.

1 files changed, 9 insertions, 16 deletions

diff --git a/django/db/backends/postgresql/operations.py b/django/db/backends/postgresql/operations.py
index dd422af1af..70880d4179 100644
--- a/django/db/backends/postgresql/operations.py
+++ b/django/db/backends/postgresql/operations.py
@@ -117,28 +117,21 @@ class DatabaseOperations(BaseDatabaseOperations):
     def set_time_zone_sql(self):
         return "SET TIME ZONE %s"
 
-    def sql_flush(self, style, tables, sequences, allow_cascade=False):
+    def sql_flush(self, style, tables, *, reset_sequences=False, allow_cascade=False):
         if not tables:
             return []
 
         # Perform a single SQL 'TRUNCATE x, y, z...;' statement. It allows us
         # to truncate tables referenced by a foreign key in any other table.
-        tables_sql = ', '.join(
-            style.SQL_FIELD(self.quote_name(table)) for table in tables
-        )
+        sql_parts = [
+            style.SQL_KEYWORD('TRUNCATE'),
+            ', '.join(style.SQL_FIELD(self.quote_name(table)) for table in tables),
+        ]
+        if reset_sequences:
+            sql_parts.append(style.SQL_KEYWORD('RESTART IDENTITY'))
         if allow_cascade:
-            sql = ['%s %s %s;' % (
-                style.SQL_KEYWORD('TRUNCATE'),
-                tables_sql,
-                style.SQL_KEYWORD('CASCADE'),
-            )]
-        else:
-            sql = ['%s %s;' % (
-                style.SQL_KEYWORD('TRUNCATE'),
-                tables_sql,
-            )]
-        sql.extend(self.sequence_reset_by_name_sql(style, sequences))
-        return sql
+            sql_parts.append(style.SQL_KEYWORD('CASCADE'))
+        return ['%s;' % ' '.join(sql_parts)]
 
     def sequence_reset_by_name_sql(self, style, sequences):
         # 'ALTER SEQUENCE sequence_name RESTART WITH 1;'... style SQL statements