Fixed #30595 -- Added error message when no objects found to sql* management commands.

django/core/management/commands/sqlflush.py

@@ -19,4 +19,7 @@ class Command(BaseCommand):
         )
 
     def handle(self, **options):
-        return '\n'.join(sql_flush(self.style, connections[options['database']], only_django=True))
+        sql_statements = sql_flush(self.style, connections[options['database']], only_django=True)
+        if not sql_statements and options['verbosity'] >= 1:
+            self.stderr.write('No tables found.')
+        return '\n'.join(sql_statements)

django/core/management/commands/sqlmigrate.py

@@ -63,4 +63,6 @@ class Command(BaseCommand):
         # for it
         plan = [(executor.loader.graph.nodes[targets[0]], options['backwards'])]
         sql_statements = executor.collect_sql(plan)
+        if not sql_statements and options['verbosity'] >= 1:
+            self.stderr.write('No operations found.')
         return '\n'.join(sql_statements)

django/core/management/commands/sqlsequencereset.py

@@ -20,4 +20,6 @@ class Command(AppCommand):
         connection = connections[options['database']]
         models = app_config.get_models(include_auto_created=True)
         statements = connection.ops.sequence_reset_sql(self.style, models)
+        if not statements and options['verbosity'] >= 1:
+            self.stderr.write('No sequences found.')
         return '\n'.join(statements)

tests/empty_models/test_commands.py

@@ -0,0 +1,18 @@
+import io
+
+from django.core.management import call_command
+from django.test import TestCase
+
+
+class CoreCommandsNoOutputTests(TestCase):
+    available_apps = ['empty_models']
+
+    def test_sqlflush_no_tables(self):
+        err = io.StringIO()
+        call_command('sqlflush', stderr=err)
+        self.assertEqual(err.getvalue(), 'No tables found.\n')
+
+    def test_sqlsequencereset_no_sequences(self):
+        err = io.StringIO()
+        call_command('sqlsequencereset', 'empty_models', stderr=err)
+        self.assertEqual(err.getvalue(), 'No sequences found.\n')

tests/migrations/test_commands.py

@@ -645,6 +645,12 @@ class MigrateTests(MigrationTestBase):
             self.assertNotIn(start_transaction_sql.lower(), queries)
         self.assertNotIn(connection.ops.end_transaction_sql().lower(), queries)
 
+    @override_settings(MIGRATION_MODULES={'migrations': 'migrations.test_migrations_no_operations'})
+    def test_migrations_no_operations(self):
+        err = io.StringIO()
+        call_command('sqlmigrate', 'migrations', '0001_initial', stderr=err)
+        self.assertEqual(err.getvalue(), 'No operations found.\n')
+
     @override_settings(
         INSTALLED_APPS=[
             "migrations.migrations_test_apps.migrated_app",

tests/migrations/test_migrations_no_operations/0001_initial.py

@@ -0,0 +1,6 @@
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    dependencies = []
+    operations = []