使用 Django South 将自动增量字段添加到现有模型中？
我有一个 Django 项目，最初是作为旧数据库的导入而开始的。因此，出现了具有复合主键的模型。只要我只使用旧数据，这种方法就有效，但现在我想添加新数据，而我创建的表单告诉我，我正在尝试插入重复数据，大概是因为它只将其中一个字段视为主键。
现在我想更改模型以使用自动增量主键，就像 Django 会自动添加一样。我尝试从字段中删除主键属性并将它们放入 Meta 内部类中的 unique_together 中。当我使用 South 运行 schemamigration 时，它想要按预期添加一个 id 字段，但它要求提供默认值。
如何指定 South 应以对自动增量字段合理的方式分配唯一键？ （即将序列 [1...n] 分配给记录的任意顺序）
如果这是不可能的，是否有另一种方法可以完成相同的事情，最好使用 Django 和 South？
I have a Django project that started as an import of a legacy database. Because of this, there is a model with a composite primary key. This worked as long as I used only the legacy data, but now I want to add new data and the form I created is telling me that I am trying to insert duplicate data, presumably because it is only looking at one of the fields as the primary key.
Now I want to change the model to use an autoincrement primary key, like one Django would automatically add. I tried removing the primary key attributes from the fields and putting them in unique_together in the Meta inner class. When I ran schemamigration with South, it wanted to add an id field as expected, but it asked for a default value.
How can I specify that South should assign unique keys in some way that is reasonable for an autoincrement field? (i.e. assign the sequence [1...n] to some arbitrary ordering of the records)
If this is impossible is there another way to accomplish the same thing, preferably using Django and South?
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我通过解决方法解决了需要执行此操作的问题：
我使用
INSERT INTO...SELECT...将原始表中的数据复制到 SQL 中的临时表中。然后我删除了原始表并使用自动增量字段重新创建了它。然后，我将数据复制回新表中，并通过 INSERT 命令自动添加自动增量值。最后，我执行了一次 South 迁移的假运行，以使 South 的表与新架构保持一致。I solved the problem that required me to do this with a workaround:
I copied the data from the original table into a temporary table in SQL with
INSERT INTO... SELECT.... I then deleted the original table and recreated it with the autoincrement field. Then I copied the data back into the new table, with the autoincrement values added automatically by theINSERTcommand. Finally I executed a fake run of the South migration to make South's tables consistent with the new schema.