diff options
Diffstat (limited to 'django/db/models/sql')
| -rw-r--r-- | django/db/models/sql/compiler.py | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/django/db/models/sql/compiler.py b/django/db/models/sql/compiler.py index 2543755952..6874ae6ef4 100644 --- a/django/db/models/sql/compiler.py +++ b/django/db/models/sql/compiler.py @@ -523,6 +523,31 @@ class SQLCompiler: if for_update_part and not self.connection.features.for_update_after_from: result.append(for_update_part) + if self.query.subquery and extra_select: + # If the query is used as a subquery, the extra selects would + # result in more columns than the left-hand side expression is + # expecting. This can happen when a subquery uses a combination + # of order_by() and distinct(), forcing the ordering expressions + # to be selected as well. Wrap the query in another subquery + # to exclude extraneous selects. + sub_selects = [] + sub_params = [] + for select, _, alias in self.select: + if alias: + sub_selects.append("%s.%s" % ( + self.connection.ops.quote_name('subquery'), + self.connection.ops.quote_name(alias), + )) + else: + select_clone = select.relabeled_clone({select.alias: 'subquery'}) + subselect, subparams = select_clone.as_sql(self, self.connection) + sub_selects.append(subselect) + sub_params.extend(subparams) + return 'SELECT %s FROM (%s) AS subquery' % ( + ', '.join(sub_selects), + ' '.join(result), + ), sub_params + params + return ' '.join(result), tuple(params) finally: # Finally do cleanup - get rid of the joins we created above. |