Ruby-on-rails 在 PostgreSQL 中强制字符串的最大长度
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Force max length for string in PostgreSQL
提问by Jimmy
I am using heroku for a RoR application and am trying to manually set the length of a string column and am having trouble.
我正在将 heroku 用于 RoR 应用程序，并尝试手动设置字符串列的长度，但遇到了问题。
I tried making a migration along the lines of
我尝试按照以下方式进行迁移
change_column :posts, :content, :string, :length => 10000
I assumed this would work but no such luck, anyone have some pointers?
我认为这会奏效，但没有这样的运气，有人有指点吗？
Thanks!
谢谢！
回答by Jason Weathered
The length limit option in Rails migrations is called :limit:
Rails 迁移中的长度限制选项称为:limit：
change_column :posts, :content, :string, :limit => 10000
If you are finding yourself changing VARCHARlength limits a lot, you might want to read @depesz's blog post on VARCHARvs TEXT.
如果您发现自己经常更改VARCHAR长度限制，则可能需要阅读 @depesz 在VARCHARvsTEXT上的博客文章。
