ruby-on-rails - 当列与表不匹配时，如何可逆地删除表上的remove_foreign_key？

Question

我尝试了以下方法

remove_foreign_key :users, :asset_types, column: :seek_asset_type_id

但出现错误

StandardError: An error has occurred, this and all later migrations canceled:
wrong number of arguments (given 3, expected 1..2)

文档说它使用与#add_foreign_key相同的选项。

Documentation

该列是之前创建的

add_reference :users, :seek_asset_type, foreign_key: {to_table: :asset_types}

这是定义:

"fk_rails_4dcaa1c59c" FOREIGN KEY (seek_asset_type_id) REFERENCES asset_types(id)

Answer 1

使用revert :

def change
  revert do
    add_reference :users, :seek_asset_type, foreign_key: { to_table: :asset_types }
  end
end

另一种方法是通过名称恢复迁移:

def change
  revert AddAssetTypeReferenceToUsers 
  # I made up this migration name, 
  # so please fill in the appropriate name
end