In Django, queries are generated with "::text" casting, how can I turn that off?

SELECT "snore_notification"."id", "snore_notification"."acknowledged",
"snore_notification"."active", "snore_notification"."classname", 
"snore_notification"."elementclass", "snore_notification"."elementname", 
"snore_notification"."event", "snore_notification"."eventtext", 
"snore_notification"."firstnotified", "snore_notification"."lastnotified", 
"snore_notification"."lastcleared", "snore_notification"."lastchanged", 
"snore_notification"."inserttime", "snore_notification"."instance", 
"snore_notification"."impact", "snore_notification"."isroot", 
"snore_notification"."isproblem", "snore_notification"."name", 
"snore_notification"."notificationtype", "snore_notification"."owner", 
"snore_notification"."severity", "snore_notification"."sourcedomain", 
"snore_notification"."troubleticketid", "snore_notification"."userdefined1",
"snore_notification"."开发者_运维百科userdefined2", "snore_notification"."userdefined3", 
"snore_notification"."userdefined4", "snore_notification"."userdefined5", 
"snore_notification"."userdefined6", "snore_notification"."userdefined7", 
"snore_notification"."userdefined8", "snore_notification"."userdefined9", 
"snore_notification"."userdefined10", "snore_notification"."instancedisplayname", 
"snore_notification"."counts" FROM "snore_notification" WHERE 
("snore_notification"."firstnotified" BETWEEN 2011-01-03 00:00:00 and 2011-01-03 
23:59:59 AND ("snore_notification"."instance"::text LIKE %OPEN% OR 
"snore_notification"."elementname" = OPEN OR 
"snore_notification"."troubleticketid"::text LIKE %OPEN% OR 
"snore_notification"."userdefined2" = OPEN ))';

They code that generated this query is

Notification.objects.filter(Q(firstnotified__range=(beginstring,  endstring)),Q(instance__contains=i)|Q(elementname=i)|Q(troubleticketid__contains=i)|Q(userdefined2=i))

I'm connecting to a Vertica database that doesn't like the ::text casting. Is there a way to disable this?

If you implement your own database backend that extends the PostgreSQL backend than you can change it.

the ::text is hardcoded in the lookup_cast method in the DatabaseOperations class.

Source: http://code.djangoproject.com/browser/django/trunk/django/db/backends/postgresql/operations.py#L60