id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
27826	Django migration can not find existing constraint	Michal Čihař	nobody	"I've a project with long history. The databases were originally migrated by South and then it has moved to Django migrations.

Now when I've made changes to unique_together constraint, I got migration failure:

{{{
ValueError: Found wrong number (0) of constraints for trans_check(contentsum, project_id, language_id, check)
}}}

This seems to be caused by the constraing being created in different order in past. I think it has been created by South, but I'm not 100% sure. But anyway I've ended up with half applied migration what is not really a pleasant state.

I've fixed this for me by comparing fields as set not as lists (see attached patch), what is certainly okay for unique constraints, but is probably bad idea for general indexes."	Uncategorized	closed	Uncategorized	1.10	Normal	duplicate			Unreviewed	0	0	0	0	0	0