通过生成迁移向 ruby on rails 中的列添加索引 :unique
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Adding index :unique to a column in ruby on rails via generate migration
提问by Denny Mueller
I know that i can touch a migration and add
我知道我可以触摸迁移并添加
add_index :table_name, :column_name, :unique => true
But how is the right rails migration command to generate this?
但是正确的 rails 迁移命令是如何生成这个的呢？
rails g migration add_index_to_column_name :column_name, :unique => true
Is that right?
那正确吗？
In my special example I have a table customers
在我的特殊示例中，我有一个表客户
t.integer :customerID
t.string :surname
t.string :first_name
t.string :phone
an i want to set the customerID to unique. Tried
我想将 customerID 设置为唯一的。试过
rails g migration AddIndexToCustomers :customerID, :unique => true
But if i look to my migration file after this, it dont look right see this:
但是如果我在此之后查看我的迁移文件，它看起来不正确，看到这个：
def change
add_column :customers, :, :customerID,
add_column :customers, :, :unique
add_column :customers, :=, :string
end
Any idea or suggestion?
有什么想法或建议吗？
回答by ck3g
Starting from Rails 3.2 you able to use:
从 Rails 3.2 开始，您可以使用：
rails g migration add_index_to_table_name column_name:uniq
example from http://guides.rubyonrails.org/3_2_release_notes.html
来自http://guides.rubyonrails.org/3_2_release_notes.html 的示例
rails g scaffold Post title:string:index author:uniq price:decimal{7,2}
updI'm sorry. The default type if you don't pass it would be string. You can pass type by yourself.
upd对不起。如果你不传递它的默认类型将是字符串。你可以自己传递类型。
column_name:type:uniq
Thus your example should looks like:
因此，您的示例应如下所示：
rails g migration add_index_to_customers customerID:integer:uniq
