Peewee迁移-外键约束？

Question

I have searched and there are no questions here dealing with this. I have some tables defined in my migrations like so -

from playhouse.migrate import * 

db = MySQLDatabase('mydb', 'root', 'password', 'localhost', 3306)

migrator = MySQLMigrator(db)

id_field = IntegerField(null=False, unique=True, index=True, primary_key=True)

fk_field = IntegerField(null=False)

with db.atomic():
    migrate(
        migrator.add_column('my_table', 'id', id_field)
    )

with db.atomic():
        migrate(
            migrator.add_column('my_table1', 'id', id_field)
            migrator.add_column('my_table1', 'table_id', fk_field) # this needs to be marked as a foreign key constraint somehow?
        )

However, the documentation makes it very unclear how to specify in the migrations a foreign key constraint. A ForeignKeyField seems to require a model which I do not have.

Is there a way to specify in the migrations that table_id is a foreign key that relates to the my_table id field? You would do this using FOREIGN KEY table_id REFERENCES my_table(id) in standard SQL.

Im at a loss and I'm about to dump my migrations for SQL because peewee's documentation doesn't really make this clear. I am not using Django - I have just bolted on peewee to a few scripts I have.

What can I do to remedy this so migrations fully define my models?

Answer 1

If you are trying to add a foreign-key to a model you do not "have", there are a couple ways. You could create a stub model to stand as a placeholder for the target of the foreign-key, and then call add_column() with a ForeignKeyField . Or you could specify a list of constraints explicitly in the IntegerField() :

field = IntegerField(..., constraints=[SQL('foreign key references foo(bar)')])