Retrieving FK table values from a .get() and not using .filter()

Using Django Using the ORM
1

I have to use .get() because there’s a lot of code that follows using dot notation.

sof = ServiceOrder.objects.get(id=sof_id)
    if sof is None:
        return ['Service Order ID does not exist']

but it seems that I can get FK fields from .filter() only ? ('acc_manager__emp_name')

    sof = ServiceOrder.objects.get(id=sof_id).values(
        'so_number', 'status',
        'acc_manager__emp_name'
    ).first()
    if not sof:
        return ['Service Order ID does not exist']

How do I extract acc_manager__emp_name from get() so that I can reference sof.acc_manager__emp_name ?

2

The filter and values functions return querysets, get returns an instance of the model.

If you’re chaining query api functions, the function not returning a queryset must be the last function call in the list.

In other words, it’s valid to do something like:
SomeModel.objects.values(...).get(...)

It’s also redundant to use both first and get in a query. The first function also returns an instance.

For what you have, simply replacing get with filter should do what you need it to do.

3

In Django ORM, backward and forward relations are available on all objects.

sof = ServiceOrder.objects.get(id=sof_id)

after you get the sof object, just follow the relation

emp_name = sof.acc_manager.emp_name

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