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
34298	drop constraint if exists	sahaliyev	nobody	"Hi there, 

Today encountered a problem, where Django migrate fails to drop constraint that actually does not exists. 
Here is the scenario. 
I created constraint  via migration and then go to db and manually drop constraint and also changed my code. 
Here, new migration file is generated to drop constraint, however, constraint already dropped. 
In this case, migration is giving error. 
It would be great just try to drop constraint and if not exists just pass. 
As PostgreSQL has this functionality, drop constraint if exists. 
Django can also use this. "	New feature	closed	Core (Management commands)	4.1	Normal	wontfix			Unreviewed	0	0	0	0	0	0