diff options
| -rw-r--r-- | django/db/models/sql/query.py | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py index 296eb285e1..62a5670af8 100644 --- a/django/db/models/sql/query.py +++ b/django/db/models/sql/query.py @@ -652,7 +652,7 @@ class Query(object): data[LHS_ALIAS] = change_map[lhs] self.alias_map[alias] = tuple(data) - def bump_prefix(self): + def bump_prefix(self, exceptions=()): """ Changes the alias prefix to the next letter in the alphabet and relabels all the aliases. Even tables that previously had no alias will @@ -661,12 +661,17 @@ class Query(object): Subclasses who create their own prefix should override this method to produce a similar result (a new prefix and relabelled aliases). + + The 'exceptions' parameter is a container that holds alias names which + should not be changed. """ assert ord(self.alias_prefix) < ord('Z') self.alias_prefix = chr(ord(self.alias_prefix) + 1) change_map = {} prefix = self.alias_prefix for pos, alias in enumerate(self.tables): + if alias in exceptions: + continue new_alias = '%s%d' % (prefix, pos) change_map[alias] = new_alias self.tables[pos] = new_alias |