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diff --git a/guides/source/association_basics.md b/guides/source/association_basics.md index c0fa3cfd04..1191f5edfe 100644 --- a/guides/source/association_basics.md +++ b/guides/source/association_basics.md @@ -622,6 +622,19 @@ end We pass `id: false` to `create_table` because that table does not represent a model. That's required for the association to work properly. If you observe any strange behavior in a `has_and_belongs_to_many` association like mangled model IDs, or exceptions about conflicting IDs, chances are you forgot that bit. +You can also use the method `create_join_table` + +```ruby +class CreateAssembliesPartsJoinTable < ActiveRecord::Migration + def change + create_join_table :assemblies, :parts do |t| + t.index :assembly_id + t.index :part_id + end + end +end +``` + ### Controlling Association Scope By default, associations look for objects only within the current module's scope. This can be important when you declare Active Record models within a module. For example: |