Question

In Rails 3.2, on a User show page I’m trying to display a list of Users that user has liked or tagged.

@user = User.find(params[:id])
@users = User.where(( id: @user.tags.uniq.map(&:user_id)) | (id: @user.likes.uniq.map(&:user_id)) )

This is giving a syntax error. I’ve tried a few other permutations, but no luck.

What is the correct syntax to perform an OR query on two associations?

Thanks

Answer 1

As you are using the id column for both queries you can combine the ids of both @user.tags and @user.likes before doing a find.

@user = User.find(params[:id])
user_ids = (@user.tags.map(&:user_id) + @user.likes.map(&:user_id))
@users = User.find(user_ids.uniq)

You can probably refine this even more but this looks easier to understand to me.