Drop hstore required constraint only if exists

Photonios · Photonios · commit 94f005ad54ef · 2018-06-19T16:11:36.000+03:00
Without it we create a problem for projects which are upgrading from a
version of django-postgres-extra where required constraints were not
enforced on a DB level.
diff --git a/psqlextra/backend/hstore_required.py b/psqlextra/backend/hstore_required.py
@@ -19,7 +19,7 @@ class HStoreRequiredSchemaEditorMixin:
 
     sql_hstore_required_drop = (
         'ALTER TABLE {table} '
-        'DROP CONSTRAINT {name}'
+        'DROP CONSTRAINT IF EXISTS {name}'
     )
 
     def create_model(self, model):

Original file line number	Diff line number	Diff line change
`@@ -19,7 +19,7 @@ class HStoreRequiredSchemaEditorMixin:`
`19`	`19`
`20`	`20`	`sql_hstore_required_drop = (`
`21`	`21`	`'ALTER TABLE {table} '`
`22`		`- 'DROP CONSTRAINT {name}'`
	`22`	`+ 'DROP CONSTRAINT IF EXISTS {name}'`
`23`	`23`	`)`
`24`	`24`
`25`	`25`	`def create_model(self, model):`