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activerecord - varchar Migration question for Ruby on Rails

I have created a new table including a column "note". The default is varchar(255) I believe but I wish to have this column be a text area vs. a field and to allow more data. I imagine that I would make this change in ActiveRecord::Migration file but I am curious as to the format. Do I simply change the varchar(255) to varchar(1000) for example? (if so what is the format?

def self.up
    create_table :notes do |t|
      t.string :note :varchar(1000)
    end

Is that the right format? Furthermore, how do I get the entry field to be multiple rows. Sorry if this is easy stuff but I am new to programming and RoR. Thanks.

question from:https://stackoverflow.com/questions/1663020/varchar-migration-question-for-ruby-on-rails

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You can simply use the 'text' type instead of 'string'.

def self.up
  create_table :notes do |t|
    t.text :note
  end
end

Using the 'text' type will result in database column of type TEXT. Varchar is usually limited to a maximum length of 255 (in MySQL, other RDBMSs have similar limits).

If you use Rails' form helpers, a textarea will be output for this field (because it is of type 'text'). textarea is the form element that accepts multi-line input.

Edit: If you've already migrated the create_table, you can create a new migration to change the column type:

def self.up
  change_column :notes, :note, :text
end

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