unique_together中的多个元组

问题描述

当我定义一个模型并在Meta中使用unique_together时，我可以定义多个元组。这些是要进行或运算还是与运算？可以说我有一个模型，其中

When I am defining a model and using unique_together in the Meta, I can define more than one tuple. Are these going to be ORed or ANDed? That is lets say I have a model where

class MyModel(models.Model):
    druggie = ForeignKey('druggie', null=True)
    drunk = ForeignKey('drunk', null=True)
    quarts = IntegerField(null=True)
    ounces = IntegerField(null=True)

    class Meta:
        unique_together = (('drunk', 'quarts'),
                           ('druggie', 'ounces'))

药物和盎司都是唯一的，或者醉酒和夸脱都是唯一的，但不是两个。

either both druggie and ounces are unique or both drunk and quarts are unique, but not both.

推荐答案

每个元组都会在 CREATE TABLE 查询中添加一个离散的 UNIQUE 子句。这样，每个元组都是独立的，并且如果违反任何数据完整性约束，则插入将失败。

Each tuple results in a discrete UNIQUE clause being added to the CREATE TABLE query. As such, each tuple is independent and an insert will fail if any data integrity constraint is violated.

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