Django not update field when I use arrays[] for select object:

[moizes.m@…]

Django not update field when I use arrays[] for select object:

Itensvar = Itens.objects.all()
Itensvar[0].desc = 'Test'
Itensvar[0].save()

#django not execute update in database

[Karen Tracey]

Reformatted description -- please use preview to ensure your tickets are readable before submitting them.

Actually the Itensvar[0].save() will issue a database update, the problem is it will call save() on an newly-retrieved-from-the-database object, not the one you retrieved and change the desc on in the previous line. There is no caching done when you access a queryset by indexing like this. If you look at the doc here: ​http://docs.djangoproject.com/en/dev/topics/db/queries/#limiting-querysets and replace the indexing notation with what its rough equivalent is:

Itensvar[0:1].get().desc = 'Test'
Itensvar[0:1].get().save()

you can see the problem. The 2nd line isn't operating on the same object as the first one changed, it's calling save() on a new copy retrieved from the database. You need to write this as:

x = Itensvar[0]
x.desc = 'Test'
x.save()