Create a new migration and use change_column_default. http://apidock.com/rails/ActiveRecord/ConnectionAdapters/SchemaStatements/change_column_default Sets a new default value for a column: change_column_default(:suppliers, :qualification, ‘new’) change_column_default(:accounts, :authorized, 1) Setting the default to nil effectively drops the default: change_column_default(:users, :email, nil)
From the docs: def up change_column_default :table_name, :status, 0 end def down change_column_default :table_name, :status, nil end
If you previously specified a limit in a migration and want to just remove the limit, you can just do this: change_column :users, :column, :string, :limit => 255 255 is the standard length for a string column, and rails will just wipe out the limit that you previously specified. Updated: While this works in a … Read more
The second method is the ideal way to handle this: your migration files are meant to represent how your database has changed over time. The older migration files will remain in your project (in case, hypothetically, you wanted to roll back to an older version), but Rails will not run them when you rake db:migrate … Read more
Be sure that your file name and class name say the same thing(except the class name is camel cased).The contents of your migration file should look something like this, simplified them a bit too: #20090106022023_create_articles.rb class CreateArticles < ActiveRecord::Migration def self.up create_table :articles do |t| t.belongs_to :user, :category t.string :title t.text :synopsis, :limit => 1000 … Read more
looks like pg 1.0 is not compatible with rails 5.1.4 at the moment. gem ‘pg’, ‘~> 0.18’ 0.18 worked for me.
I ended up solving the problem like this: (1) Go to the branches that has the migration files and roll them back. This is not trivial when you have many branches which are will result in many conflicts if you try to merge them. So I use this commands to find out the branches of … Read more
categories_products. Both plural. In lexical order. Quote: Unless the name of the join table is explicitly specified by using the :join_table option, Active Record creates the name by using the lexical order of the class names. So a join between customer and order models will give the default join table name of “customers_orders” because “c” … Read more
Simply adding the 3rd argument (the column’s :type) to the remove_column method makes that migration reversible. So the OP’s original code actually did work, as in: remove_column :foos, :bar, :boolean The rest of this answer was an attempt to discover why this method would not have been working, but the OP ended up getting it … Read more
Rails 4.2.1 rails g migration RemoveClientFromUsers client:references Will generate a migration similar: class RemoveClientFromUser < ActiveRecord::Migration def change remove_reference :users, :client, index: true, foreign_key: true end end In addition, one is at liberty to add another or other reference(s) by adding: add_reference :users, :model_name, index: true, foreign_key: true within the very change method. And finally … Read more