Default Order

Part of the Models and the Admin section of Coddy's Django journey. Lesson 6 of 23.

Your books come back in no promised order: whatever the database gives. A model can set the order once, for every query that does not ask for another. Options for the whole model, rather than one field, go in an inner class named Meta:

class Movie(models.Model):
    ...

    class Meta:
        ordering = ["-released", "title"]

ordering is a list of field names. A name alone sorts from low to high, A to Z for text; a minus in front sorts the other way, so this lists the newest films first. The second name breaks ties: films out on the same day come A to Z.

Challenge

Easy

Make books come back in title order, A to Z, whenever no order is asked for.

Press Run and open the Data tab: the four books are listed A to Z. Book.objects.all() in the Shell tab shows the same order.

Try it yourself

from django.db import models


class Book(models.Model):
    class Genre(models.TextChoices):
        FICTION = "fiction", "Fiction"
        SCIFI = "scifi", "Science fiction"
        MYSTERY = "mystery", "Mystery"
        HISTORY = "history", "History"

    title = models.CharField(max_length=200)
    author = models.CharField(max_length=100)
    year = models.IntegerField()
    price = models.DecimalField(max_digits=6, decimal_places=2)
    is_read = models.BooleanField(default=False)
    finished = models.DateField(null=True, blank=True)
    summary = models.TextField(blank=True)
    genre = models.CharField(max_length=20, choices=Genre, default=Genre.FICTION)

    def __str__(self):
        return f"{self.title} by {self.author}"