diff options
Diffstat (limited to 'activerecord/lib/active_record/associations.rb')
| -rw-r--r-- | activerecord/lib/active_record/associations.rb | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb index 0952ea2829..34684ad2f5 100644 --- a/activerecord/lib/active_record/associations.rb +++ b/activerecord/lib/active_record/associations.rb @@ -1424,18 +1424,18 @@ module ActiveRecord # join table with a migration such as this: # # class CreateDevelopersProjectsJoinTable < ActiveRecord::Migration - # def self.up + # def change # create_table :developers_projects, :id => false do |t| # t.integer :developer_id # t.integer :project_id # end # end - # - # def self.down - # drop_table :developers_projects - # end # end # + # It's also a good idea to add indexes to each of those columns to speed up the joins process. + # However, in MySQL it is advised to add a compound index for both of the columns as MySQL only + # uses one index per table during the lookup. + # # Adds the following methods for retrieval and query: # # [collection(force_reload = false)] |