Modify migration files to add indexes and some database constraints on input size

create_boards.rb

class CreateBoards < ActiveRecord::Migration
  def self.up
    create_table :boards do |t|
      t.integer :id
      t.string :title, :limit => 50

      t.timestamps
    end
    
  end

  def self.down
    drop_table :boards
  end
end

create_comments.rb

class CreateComments < ActiveRecord::Migration
  def self.up
    create_table :comments do |t|
      t.integer :id
      t.integer :user_id
      t.integer :conversation_id
      t.text :body

      t.timestamps
    end
    add_index :comments, :conversation_id
    add_index :comments, :user_id
  end

  def self.down
    drop_table :comments
  end
end

create_conversations.rb

class CreateConversations < ActiveRecord::Migration
  def self.up
    create_table :conversations do |t|
      t.integer :id
      t.string :title, :limit => 50
      t.integer :board_id
      t.integer :user_id

      t.timestamps
    end
    add_index :conversations, :board_id
    add_index :conversations, :user_id
  end

  def self.down
    drop_table :conversations
  end
end