From e9acafd984ef64b44a8f0c998acaddbdce1dd6fb Mon Sep 17 00:00:00 2001 From: Steve Klabnik Date: Mon, 17 Sep 2012 22:03:34 +0300 Subject: Add note about inheretance and poly associations. This note came about due to discussion in #6786. --- guides/source/association_basics.textile | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'guides/source') diff --git a/guides/source/association_basics.textile b/guides/source/association_basics.textile index 151752eee9..e991a309ff 100644 --- a/guides/source/association_basics.textile +++ b/guides/source/association_basics.textile @@ -338,6 +338,10 @@ end !images/polymorphic.png(Polymorphic Association Diagram)! +Polymorphic associations can get tricky with inheritance. If you need +an inheritance relationship in your ActiveRecord models, you should use +Single Table Inheritance instead. + h4. Self Joins In designing a data model, you will sometimes find a model that should have a relation to itself. For example, you may want to store all employees in a single database model, but be able to trace relationships such as between manager and subordinates. This situation can be modeled with self-joining associations: -- cgit v1.2.3