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61 lines
1.5 KiB
Python
61 lines
1.5 KiB
Python
from django.db import models
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class Address(models.Model):
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company = models.CharField(max_length=1)
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customer_id = models.IntegerField()
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class Meta:
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unique_together = [
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("company", "customer_id"),
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]
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class Customer(models.Model):
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company = models.CharField(max_length=1)
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customer_id = models.IntegerField()
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address = models.ForeignObject(
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Address,
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models.CASCADE,
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null=True,
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# order mismatches the Contact ForeignObject.
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from_fields=["company", "customer_id"],
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to_fields=["company", "customer_id"],
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)
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class Meta:
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unique_together = [
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("company", "customer_id"),
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]
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class Contact(models.Model):
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company_code = models.CharField(max_length=1)
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customer_code = models.IntegerField()
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customer = models.ForeignObject(
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Customer,
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models.CASCADE,
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related_name="contacts",
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to_fields=["customer_id", "company"],
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from_fields=["customer_code", "company_code"],
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)
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class CustomerTab(models.Model):
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customer_id = models.IntegerField()
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customer = models.ForeignObject(
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Customer,
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from_fields=["customer_id"],
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to_fields=["id"],
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on_delete=models.CASCADE,
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)
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class Meta:
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required_db_features = {"supports_table_check_constraints"}
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constraints = [
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models.CheckConstraint(
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condition=models.Q(customer__lt=1000),
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name="customer_id_limit",
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),
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]
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