diff options
| -rw-r--r-- | django/db/models/query.py | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/django/db/models/query.py b/django/db/models/query.py index dc1ddf1606..da4c69f362 100644 --- a/django/db/models/query.py +++ b/django/db/models/query.py @@ -1418,8 +1418,15 @@ def get_cached_row(row, index_start, using, klass_info, offset=0): fields = row[index_start : index_start + field_count] # If all the select_related columns are None, then the related # object must be non-existent - set the relation to None. - # Otherwise, construct the related object. - if fields == (None,) * field_count: + # Otherwise, construct the related object. Also, some backends treat '' + # and None equivalently for char fields, so we have to be prepared for + # '' values. + if connections[using].features.interprets_empty_strings_as_nulls: + vals = tuple([None if f == '' else f for f in fields]) + else: + vals = fields + + if vals == (None,) * field_count: obj = None else: if field_names: |