| 38 | 2. |
| 39 | Consider the following models: |
| 40 | |
| 41 | {{{ |
| 42 | class A(models.Model): |
| 43 | field1 = models.IntegerField() |
| 44 | |
| 45 | class B(A): |
| 46 | field2 = models.IntegerField() |
| 47 | |
| 48 | class C(B): |
| 49 | field_c = models.IntegerField() |
| 50 | }}} |
| 51 | |
| 52 | {{{ |
| 53 | queryset = C.objects.all().select_for_update(of=('b_ptr', 'b_ptr__a_ptr')) |
| 54 | }}} |
| 55 | |
| 56 | The above queryset crashes with the following crashlog: |
| 57 | |
| 58 | {{{ |
| 59 | Traceback (most recent call last): |
| 60 | File "/home/abhijeet/git-repos/django/django/core/management/base.py", line 328, in run_from_argv |
| 61 | self.execute(*args, **cmd_options) |
| 62 | File "/home/abhijeet/git-repos/django/django/core/management/base.py", line 369, in execute |
| 63 | output = self.handle(*args, **options) |
| 64 | File "/home/abhijeet/django_contrib/selectforupdate/management/commands/debug.py", line 12, in handle |
| 65 | print(queryset.query) |
| 66 | File "/home/abhijeet/git-repos/django/django/db/models/sql/query.py", line 257, in __str__ |
| 67 | sql, params = self.sql_with_params() |
| 68 | File "/home/abhijeet/git-repos/django/django/db/models/sql/query.py", line 265, in sql_with_params |
| 69 | return self.get_compiler(DEFAULT_DB_ALIAS).as_sql() |
| 70 | File "/home/abhijeet/git-repos/django/django/db/models/sql/compiler.py", line 555, in as_sql |
| 71 | of=self.get_select_for_update_of_arguments(), |
| 72 | File "/home/abhijeet/git-repos/django/django/db/models/sql/compiler.py", line 1036, in get_select_for_update_of_arguments |
| 73 | select_index = klass_info['select_fields'][0] |
| 74 | IndexError: list index out of range |
| 75 | }}} |
| 76 | |