If Rails doesn’t understand the column type, it’ll pass it straight through to the database. So if you want a char instead of varchar, just replace: t.column :token, :string With: t.column :token, “char(12)” Of course, this may or may not make your migrations non-portable to another database. (credit to http://laurelfan.com/2010/1/26/special-mysql-types-in-rails-migrations)
You must remove your index with: remove_index :profile_pictures, :picture_id and add it again with: add_index :profile_pictures, :picture_id ActiveRecord::Migration
The correct format would be t.string :note, :limit => 1000 make sure you are using a version of MySQL(or whichever database) which supports varchars longer than 256 characters. if you want to use a large text block it would be t.text :note See http://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/TableDefinition.html for more information
From Rails 4 upwards, the index removes automatically with the column removal.
The Answer The oft repeated answer, which tends to always be the case more often than not is, “it depends.” More specifically, it depends on what your data is and how it will be used. tl;dr Explanation The short tl;dr answer for my specific case (and to cover all future bases) is choice #2 which … Read more
You can’t: https://guides.rubyonrails.org/active_record_migrations.html#column-modifiers null and default cannot be specified via command line. The only solution is to modify the migration after it’s generated. It was the case in Rails 3, still the case in Rails 7
If you are dealing with production-grade systems then yes, it is very bad. If it is your own pet project, then anything is allowed (if nothing else, it will be a learning experience 🙂 though chances are that sooner rather than later, even in a pet project, you will find yourself having put a cross … Read more
I think you should fix the offending migrations to be less fragile, I’d guess that a couple of if statements and perhaps a rescue would be sufficient. But, if fixing the migrations really isn’t an option, you can fake it in various ways. First of all, you could just comment out the migration methods, run … Read more
Even more shorter call ActiveRecord::Base.connection.adapter_name == ‘MySQL’
You can use the index_exists? method within your migration to test whether the index you need to remove is actually there. Take a look at the documentation here: http://apidock.com/rails/ActiveRecord/ConnectionAdapters/SchemaStatements/index_exists%3F I’ve not tested it, but you should be able to use something like this: class AddTimestampIndexes < ActiveRecord::Migration def up remove_index :books, :created_at if index_exists?(:books, :created_at) … Read more