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
14462	Aggregates default to the database type instead of the field type	Wolph	Greg Wogan-Browne	"First a little background information, I've got a couple of custom field types which get cast right after loading the model.
So instead of a Decimal I get a Euro object with added features like formatting and stuff like that.

However, it seems that the aggregate/annotate queries in Django do not respect the `to_python()` method but simply cast to the type specified by the database backend.
This can easily be fixed by modifying `convert_values()` so it returns this:
{{{
#!python
return field.to_python(connection.ops.convert_values(value, field))
}}}

instead of
{{{
#!python
return connection.ops.convert_values(value, field)
}}}

The `convert_values()` function: http://code.djangoproject.com/browser/django/trunk/django/db/models/sql/query.py#L298


Would this be the proper location to fix this? Either way, it has to be a bug that the `max()` of a value returns a different type."	Bug	closed	Database layer (models, ORM)	1.2	Normal	fixed	aggregate, annotate, type, coerce	rick@…	Accepted	0	0	0	0	0	0