# 20110831¶

Fixed.

## c) Adapted dpy Deserializer to new Django version¶

One user reports the following error message during initdb:

django.db.utils.IntegrityError: (1217, 'Cannot delete or update a parent row: a foreign key constraint fails')


No explanation yet. Ticket docs/tickets/50

But after updating my Django copy from 1.4 pre-alpha SVN-16376 to 16714, I realized that the new Django version doesn’t any longer allow a trick which I used in lino.utils.dpy.Deserializer. So I had to redesign this. The new design should also work with older Django versions.

## d) dpy dumps failed to load¶

Aha, there are now two app_labels who have an EventType model: cal and notes. That leads to a name conflict in dpy dumps. Fixed.

New abstract model lino.modlib.cal.CalendarRelated is only because I was hesitating which components should have a calendar field.