Question

Im trying to display recently added comments from tattoos a user has posted. So If I posted a tattoo, and then user_b posted “hey I like your tattoo” then Im trying to get just the comment.

First of all Im using the acts_as_commentable_with_threading gem which doesnt create a foreign key for the table im trying to join. So my controller cant look for tattoo_id, it has to look for commentable_id

In the controller I would have to call the Comment model and then pass some SQL stuff into it but apparently I have no clue how to pass custom SQL queries into ruby because even tho my query string works in terminal, I get all sorts of nonsense when trying to use it in rails.

Im basically trying to do this:

SELECT comments.id FROM comments,tattoos WHERE commentable_id = tattoos.id AND 
tattoos.member_id = #{current_user}

where #{current_user} will be the current_user passed in.

Answer 1

I think Ben’s approach is best but for future reference if you do come across something more complicated you can always use sql for example:

Comment.find_by_sql("SELECT comments.* FROM comments,tattoos WHERE commentable_id = tattoos.id AND tattoos.member_id = ?", current_user)