Can ActiveRecord create tables outside of a migration?

I am working on a non Rails web app, so no migrations script by default.

The Sequel ORM lets me create tables easily in a script:

#!/usr/bin/env ruby

require 'rubygems'
require 'sequel'

## Connect to the database
DB = Sequel.sqlite('./ex1.db')

unless DB.table_exists? :posts
  DB.create_table :posts do
    primary_key :id
    varchar :title
    text :body

Is there a way todo this with ActiveRecord outside of migrations?


My current understanding is no, all modifications data or schema have to be done through a migration. I have a complete rakefile on github which can be used to perform the migrations outside of Rails.

Alternatively if it is just an initialisation script the following could be used.

   :adapter   => 'sqlite3',
   :database  => './lesson1_AR.db'

ActiveRecord::Migration.class_eval do
  create_table :posts do |t|
        t.string  :title
        t.text :body

   create_table :people do |t|
      t.string :first_name
      t.string :last_name
      t.string :short_name

   create_table :tags do |t|
      t.string :tags

In Rails 4 at least (possibly earlier?), you can call create table directly on an ActiveRecord::ConnectionAdapters instance, using the same syntax as the migration.

You can get a connection for your database (assuming you have only one database) by calling ActiveRecord::Base.connection. So, the Ruby for your example would look like:

unless ActiveRecord::Base.connection.table_exists?(:posts)
  ActiveRecord::Base.connection.create_table :posts do |t|
    # :id is created automatically
    t.string :title
    t.text :body

Note: If you already have a model defined, and it uses the same database as the one in which you want to create the table, you can grab a connection object from there instead. For one-off table creation in the console, I'll call User.connection.create_table simply because it's less typing.

Need Your Help

How to serialize or deserialize a JSON Object to a certain depth in C#?

c# .net json serialization

I only want the first depth level of an object (I do not want any children). I am willing to use any library available. Most libraries will merely throw an exception when the recursion depth is r...

What does classname.class return?

java oop

Could anyone please explain what does SomeClassname.class return in JAVA ?? I cant understand what it does ..