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I have a model of work orders, with a field for when the work order is required by. To get a list of work orders, with those that are required early, I do this:
wo = Work_Order.objects.order_by('dateWORequired')
This works nicely, but ONLY if there is actually a value in that field. If there is no required date, then the value is None. Then, the list of work orders has all the None's at the top, and then the remaining work orders in proper order.
How can I get the None's at the bottom?
974
If you'd like to specify a custom primary key, specify primary_key=True on one of your fields. If Django sees you've explicitly set Field.primary_key , it won't add the automatic id column. Each model requires exactly one field to have primary_key=True (either explicitly declared or automatically added).
In multi-table inheritance, each model corresponds to a database table. Django creates a OneToOneField field for the relationship in the child's model to its parent. Django would include an automatically generated OneToOneField field in the Text model and create a database table for each model.
Proxy models allow us to change the Python behavior of a model without changing the database. vehicles/models.py. from django.db import models. class Car(models.Model): vin = models.CharField(max_length=17)
Django web applications access and manage data through Python objects referred to as models. Models define the structure of stored data, including the field types and possibly also their maximum size, default values, selection list options, help text for documentation, label text for forms, etc.
Django 1.11 added this as a native feature. It's a little convoluted. It is documented.
Ordered with only one field, ascending:
wo = Work_Order.objects.order_by(F('dateWORequired').asc(nulls_last=True)) Ordered using two fields, both descending:
wo = Work_Order.objects.order_by(F('dateWORequired').desc(nulls_last=True), F('anotherfield').desc(nulls_last=True)) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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