Question

我遇到了还原包含重命名表的Django（1.8.7）迁移的问题。即使它似乎能够在Postgres中重命名它，它然后尝试使用旧表名添加约束。

这是追溯：

[...]
ALTER TABLE "team_membershiprole" RENAME TO "team_leadershiprole";
[...]
ALTER TABLE "team_leadershipteammember" 
    ADD CONSTRAINT "team_l_role_id_xxx" 
    FOREIGN KEY ("role_id") REFERENCES "team_membershiprole" ("id")     
    DEFERRABLE INITIALLY DEFERRED;
[...]

COMMIT;

如果你看一下它生成的SQL，

team_membershiprole

您可以看到有# -*- coding: utf-8 -*- from __future__ import unicode_literals from django.db import models, migrations class Migration(migrations.Migration): dependencies = [ ('core', '0023_xxx'), ('team', '0009_xxx2'), ] operations = [ migrations.CreateModel( name='TeamMembership', fields=[ ('id', models.AutoField(serialize=False, auto_created=True, verbose_name='ID', primary_key=True)), ('team', models.ForeignKey(related_name='members', to='team.Team')), ('member', models.ForeignKey(to='core.Member')), ], ), migrations.RenameModel( old_name='LeadershipRole', new_name='MembershipRole', ), migrations.RemoveField( model_name='leadershipteammember', name='team', ), migrations.RemoveField( model_name='leadershipteammember', name='member', ), migrations.RemoveField( model_name='leadershipteammember', name='role', ), migrations.DeleteModel( name='LeadershipTeamMember', ), migrations.AddField( model_name='teammembership', name='role', field=models.ForeignKey(to='team.MembershipRole'), ), ]的引用，即使该表不再存在（它已重命名）。这是迁移代码：

belongs_to :company  
counter_culture :company, :column_name => Proc.new {|user| user.active? ? 'users_count' : nil }

我知道这可能是一个Django迁移错误，但是有什么方法可以解决它吗？

Answer 1

您可以覆盖Migration.unapply，以便它使用一组不同的操作。

class MyMigration(Migration):
    operations = [
        ... your operations ...
    ]
    reverse_operations = [
        ... your fixed reverse operations ...
    ]
    def unapply(self, project_state, schema_editor, collect_sql=False):
        self.operations = self.reverse_operations
        return super(MyMigration, self).unapply(..)

我没有测试过这个，但它应该给你一个想法。哦，您可能需要反转反向迁移列表，因为Django会期望它是正向迁移的列表，因此反向遍历它们。

恢复自动生成的迁移以重命名Django中的表时出错

1 个答案: