mirror of https://github.com/django/django.git
110 lines
2.7 KiB
Python
110 lines
2.7 KiB
Python
"""
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The lookup API
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This demonstrates features of the database API.
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"""
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from django.db import models
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from django.db.models.lookups import IsNull
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class Alarm(models.Model):
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desc = models.CharField(max_length=100)
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time = models.TimeField()
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def __str__(self):
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return '%s (%s)' % (self.time, self.desc)
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class Author(models.Model):
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name = models.CharField(max_length=100)
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alias = models.CharField(max_length=50, null=True, blank=True)
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class Meta:
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ordering = ('name',)
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class Article(models.Model):
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headline = models.CharField(max_length=100)
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pub_date = models.DateTimeField()
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author = models.ForeignKey(Author, models.SET_NULL, blank=True, null=True)
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slug = models.SlugField(unique=True, blank=True, null=True)
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class Meta:
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ordering = ('-pub_date', 'headline')
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def __str__(self):
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return self.headline
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class Tag(models.Model):
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articles = models.ManyToManyField(Article)
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name = models.CharField(max_length=100)
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class Meta:
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ordering = ('name',)
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class NulledTextField(models.TextField):
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def get_prep_value(self, value):
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return None if value == '' else value
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@NulledTextField.register_lookup
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class NulledTransform(models.Transform):
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lookup_name = 'nulled'
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template = 'NULL'
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@NulledTextField.register_lookup
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class IsNullWithNoneAsRHS(IsNull):
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lookup_name = 'isnull_none_rhs'
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can_use_none_as_rhs = True
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class Season(models.Model):
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year = models.PositiveSmallIntegerField()
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gt = models.IntegerField(null=True, blank=True)
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nulled_text_field = NulledTextField(null=True)
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class Meta:
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constraints = [
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models.UniqueConstraint(fields=['year'], name='season_year_unique'),
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]
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def __str__(self):
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return str(self.year)
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class Game(models.Model):
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season = models.ForeignKey(Season, models.CASCADE, related_name='games')
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home = models.CharField(max_length=100)
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away = models.CharField(max_length=100)
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class Player(models.Model):
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name = models.CharField(max_length=100)
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games = models.ManyToManyField(Game, related_name='players')
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class Product(models.Model):
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name = models.CharField(max_length=80)
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qty_target = models.DecimalField(max_digits=6, decimal_places=2)
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class Stock(models.Model):
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product = models.ForeignKey(Product, models.CASCADE)
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qty_available = models.DecimalField(max_digits=6, decimal_places=2)
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class Freebie(models.Model):
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gift_product = models.ForeignKey(Product, models.CASCADE)
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stock_id = models.IntegerField(blank=True, null=True)
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stock = models.ForeignObject(
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Stock,
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from_fields=['stock_id', 'gift_product'],
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to_fields=['id', 'product'],
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on_delete=models.CASCADE,
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)
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