Method rename_column does not rename the column in DB

Question

Solved!

Thanks to all so much. It seems was a conflict of the migration versions. I just deleted last records from the scheme_migrations table related with the column renaming. Also i deleted all migrations files in db/migrations related with the renaming.

I have a table products_images:

class CreateProductsImages < ActiveRecord::Migration
  def change
    create_table :products_images, id: false do |t|
      t.references :product
      t.references :image
      t.integer :position
    end
    add_index :products_images, [:product_id, :image_id]
    add_index :products_images, [:image_id, :product_id]
  end
end

When I have tried to start the migration to rename a column position to priority rails made migration without any errors. But no changes in DB table products_images were applied. Of course I could delete the column and create new one with another name. Just a curiosity - why? DB is SQLite.
Migrations of renaming:
variant 1

class RenamePositionToPriority < ActiveRecord::Migration
  def change
    rename_column :products_images, :position, :priority
  end
end

variant 2:

class RenamePositionToPriority < ActiveRecord::Migration
  def change
    #rename_column :products_images, :position, :priority
    change_table :products_images do |t|
      t.rename :position, :priority
    end
  end
end

rake db:rollback outputs:

DL is deprecated, please use Fiddle
==  RenamePositionToPriority: reverting =======================================
-- rename_column(:products_images, :priority, :position)
rake aborted!
An error has occurred, this and all later migrations canceled:

Missing column products_images.priorityC:in `migrate'
Tasks: TOP => db:rollback

have you did the `db:migrate`. is seed you've begun of *rollback* — Малъ Скрылевъ, Jan 31 '14 at 12:11
is seems the db says in old status. make sure that the current structore of db has `priority` column using db console interface — Малъ Скрылевъ, Jan 31 '14 at 12:34
@Малъ Скрылевъ sqlite> .header on sqlite> select * from 'products_images product_id image_id position id ---------- ---------- ---------- -- 50 19 1 1 51 19 1 8 51 20 2 9 — ElCoyote, Jan 31 '14 at 12:44

score 2 · Accepted Answer · answered Jan 31 '14 at 13:01

2

Step 1: rails g migration RenameColumn

Step 2: before rake db:migrate open migration file on /db folder

class RenameColumn < ActiveRecord::Migration

 def self.up
   rename_column :products_images, :position, :priority
 end

 def self.down
    rename_column :products_images, :priority, :position
end

end

Step 3: rake db:migrate

answered Jan 31 '14 at 13:01

KKB

558
4
18

Yes, it works! But why? May be empty method `change` affected to the behavior and its should be deleted. Thank you! But i can`t vote up -- someone took 2 my points :/ Sorry. – ElCoyote Jan 31 '14 at 13:17

score 0 · Answer 2 · answered Jan 31 '14 at 12:19

0

class RenamePositionToPriority < ActiveRecord::Migration

def self.up rename_column :products_images , :position, :priority rename_column :products_images , :position, :priority end

def self.down rename_column :products_images , :position , :priority rename_column :products_images , :position , :priority end end

can you please try this migration

answered Jan 31 '14 at 12:19

Sanket

165
6

class RenamePositionToPriority < ActiveRecord::Migration def self.up rename_column :products_images , :position, :priority end def self.down rename_column :products_images , :priority , :position end end – ElCoyote Jan 31 '14 at 12:27
I have tried that but got a same result: D:\_web\test1>rake db:migrate DL is deprecated, please use Fiddle == RenamePositionToPriority: migrating ======================================= == RenamePositionToPriority: migrated (0.0000s) ============================== – ElCoyote Jan 31 '14 at 12:28
The column name `position` of the table `products_images` in DB is old – ElCoyote Jan 31 '14 at 12:30
hye plz delete all migration related to this Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete. Delete the migration file manually. If there are pending migrations (i.e., the migration I removed was not the last one), I just perform a new rake db:migrate again and then create new one def self.up rename_column :products_images , :position, :priority rename_column :products_images , :position, :priority end def self.down rename_column :products_images , :position , :priority rename_column :products_images , :position , :priority end end – Sanket Jan 31 '14 at 13:46
Apparently it was a conflict of migrations. Thank you. All works fine! I will update the post. – ElCoyote Jan 31 '14 at 13:59
Hope so it was help for you – Sanket Jan 31 '14 at 14:05

score 0 · Answer 3 · answered Jan 31 '14 at 12:35

0

Is there any chance what you could 'change' migration code after it was run? Just to clarify couple of things: Rails has no way to 'remember' a set of changes you've made by migrations. It just creates table called schema_migrations with version column in it. Basically, this table contains a list of versions (which identify a migration).

answered Jan 31 '14 at 12:35

marvelousNinja

1,510
9
15

Unlikely. Every time i just delete last record in `schema_migration` =) – ElCoyote Jan 31 '14 at 12:48
What do you mean by 'just delete last record in schema_migration'? – marvelousNinja Jan 31 '14 at 12:54
Every time when i run rake db:migrate(note, with no errors) and see that renaming is not effected. I can`t apply rake db:rollback cuz rake could not find `priority` column. – ElCoyote Jan 31 '14 at 13:01

Method rename_column does not rename the column in DB

3 Answers3