Django orm queries with left varaible is not certain-CodePudding

I want to make a query like this:

Student.objects.filter(id= id).update(name=value)

And the value comes from the user.

But the problem is that I'm not only to update name but also update some other information like address or phone number. I don't want to create duplicated codes like:

Student.objects.filter(id= id).update(address=value)        
Student.objects.filter(id= id).update(phone_number=value)

I only want to have one line code like:

Student.objects.filter(id= id).update(XXX=XXX_value)

So I wonder if I can assign any variable to the left varaible inside update function or not.

Sorry, the left key is not a certain value. It depends on the user's post. It might be an address or just name next time. It's not a fixed value.

Thanks.

CodePudding user response：

As per update docs

You can update multiple fields — there’s no limit on how many

So the following should do

Student.objects.filter(id=id).update(address=address_value, phone_number=phone_number_value)

EDIT

left variable is not a fixed item. It could be address or just be phone_number

In that case populate a dict dynamically and then unpack it in update. See an example below (your conditions may be of course different).

fields_to_update = {}

if address_value:
    fields_to_update["address"] = address_value

if phone_number_value:
    fields_to_update["phone_number"] = phone_number_value

Student.objects.filter(id=id).update(**fields_to_update)

Another alternative is to not use update but to work with a Student instance directly.

student = Student.objects.get(id=id)

if address_value:
    student.address = address_value

if phone_number_value:
    student.phone_number = phone_number_value

student.save()

Be aware that student = Student.objects.get(id=id) can raise DoesNotExist if a student with the given id is not found.

CodePudding user response：

You can dynamically define the fields by providing them in a dictionary and using ** to unpack the dictionary into arguments for update().

fields_to_update = {
    "address": address_value,
    "phone_number": phonenumber_value,
}
Students.objects.filter(id=update_id).update(**fields_to_update)