Postgres：列（字符串）的默认值无法自动转换为枚举类型

I have a status column in a table that I want to be an enum. Originally I created that field as an integer, thinking that I would use the built in Rails enum functionality. Turns out that requires at least Rails 4.1, but I am using 4.0 and the process of upgrading is going to take some time. column in a table that I want t