Ok so I have a senario... I have created 2 content types:
The review content type has an entity reference field which links to the cars content type. Im using the entity prepopulate module also and provided the add review link on the cars nodes however I only want users to be able to create one review per car. So I want them to be able to multiple reviews but only one for BMW, one for Honda etc.
Is there anything in using the rules module for this? has anyone else had to do something similar?