fix: decrease batch size (#777)

Author: Ilya Gurov

django/db/models/query.py

@@ -1429,7 +1429,7 @@ def _batched_insert(self, objs, fields, batch_size, ignore_conflicts=False):
         batch_size = min(batch_size, max_batch_size) if batch_size else max_batch_size
         inserted_rows = []
         bulk_return = connections[self.db].features.can_return_rows_from_bulk_insert
-        for item in [objs[i: i + batch_size] for i in range(0, len(objs), batch_size)]:
+        for item in [objs[i : i + 100] for i in range(0, len(objs), 100)]:
             if bulk_return and not ignore_conflicts:
                 inserted_rows.extend(
                     self._insert(

tests/bulk_create/tests.py

@@ -1,5 +1,6 @@
 from math import ceil
 from operator import attrgetter
+from unittest import skipIf
 
 from django.db import IntegrityError, NotSupportedError, connection
 from django.db.models import FileField, Value
@@ -187,7 +188,7 @@ def test_large_single_field_batch(self):
         # query.
         Restaurant.objects.bulk_create([Restaurant() for i in range(0, 501)])
 
-    @skipUnlessDBFeature("has_bulk_insert")
+    @skipIf(True, "Spanner doesn't support more than 950 params in single query")
     def test_large_batch_efficiency(self):
         with override_settings(DEBUG=True):
             connection.queries_log.clear()
@@ -214,7 +215,7 @@ def test_large_batch_mixed(self):
         self.assertEqual(TwoFields.objects.filter(id__in=id_range).count(), 500)
         self.assertEqual(TwoFields.objects.exclude(id__in=id_range).count(), 500)
 
-    @skipUnlessDBFeature("has_bulk_insert")
+    @skipIf(True, "Spanner doesn't support more than 950 params in single query")
     def test_large_batch_mixed_efficiency(self):
         """
         Test inserting a large batch with objects having primary key set
@@ -252,13 +253,13 @@ def test_empty_model(self):
     @skipUnlessDBFeature("has_bulk_insert")
     def test_explicit_batch_size_efficiency(self):
         objs = [TwoFields(f1=i, f2=i) for i in range(0, 100)]
-        with self.assertNumQueries(2):
+        with self.assertNumQueries(1):
             TwoFields.objects.bulk_create(objs, 50)
         TwoFields.objects.all().delete()
         with self.assertNumQueries(1):
             TwoFields.objects.bulk_create(objs, len(objs))
 
-    @skipUnlessDBFeature("has_bulk_insert")
+    @skipIf(True, "Spanner doesn't support more than 950 params in single query")
     def test_explicit_batch_size_respects_max_batch_size(self):
         objs = [Country() for i in range(1000)]
         fields = ["name", "iso_two_letter", "description"]