Learn How Can You Change DB Migration Rename in Ruby on Rails

Learn How Can You Change DB Migration Rename in Ruby on Rails

rename_column :table, :old_column, :new_column

Update:

You'll probably want to create a separate migration to do this. (Rename FixColumnName as you will)

script/generate migration FixColumnName
# creates  db/migrate/xxxxxxxxxx_fix_column_name.rb

Then edit the migration to do your will.

# db/migrate/xxxxxxxxxx_fix_column_name.rb
class FixColumnName < ActiveRecord::Migration
  def self.up
    rename_column :table_name, :old_column, :new_column
  end

  def self.down
    # rename back if you need or do something else or do nothing
  end
end

---

An update for Rails 3.1

While, the up and down methods still apply. Rails 3.1 receives a change method that "knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method"

rails g migration FixColumnName

class FixColumnName < ActiveRecord::Migration
  def change
    rename_column :table_name, :old_column, :new_column
  end
end

---

If you happen to have a whole bunch of columns to rename, or something that would have required repeating the table name over and over again.

rename_column :table_name, :old_column1, :new_column1
rename_column :table_name, :old_column2, :new_column2
...

You could use change_table to keep things a little neater.

class FixColumnNames < ActiveRecord::Migration
  def change
    change_table :table_name do |t|
      t.rename :old_column1, :new_column1
      t.rename :old_column2, :new_column2
      ...
    end
  end
end

Thank you, Luke && Turadg, for bringing up the topic.

---

Then just db:migrate as usual or however you go about your business.

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