[patch] Backslashes in LIKE queries are not escaped

[tom@…]

Say you have a model called MyModel with a TextField called text and want to get all objects where text contains a backslash. The following query, however, doesn't return anything:

models.MyModel.objects.filter(text__conatins='\\')

This query does:

models.MyModel.objects.filter(text__conatins='\\\\')

Here is a patch that fixes the problem:

Index: django/db/models/fields/__init__.py
===================================================================
--- django/db/models/fields/__init__.py (revision 3496)
+++ django/db/models/fields/__init__.py (working copy)
@@ -20,7 +20,7 @@
 BLANK_CHOICE_NONE = [("", "None")]
 
 # prepares a value for use in a LIKE query
-prep_for_like_query = lambda x: str(x).replace("%", "\%").replace("_", "\_")
+prep_for_like_query = lambda x: str(x).replace("\\", "\\\\").replace("%", "\%").replace("_", "\_")
 
 # returns the <ul> class for a given radio_admin value
 get_ul_class = lambda x: 'radiolist%s' % ((x == HORIZONTAL) and ' inline' or '')

[Adrian Holovaty]

(In [3552]) Fixed #2458 -- DB API now properly escapes backslashes, so you don't have to double-escape them. Thanks, tom@…