How to get value using join table with different values?

Question

I have a product, user and product_click model. In product_click, I have column count where I\'m keeping a record, which user click which product how many times

Answer 1

While I am thinking of other ways, one straight way would be a 2 step solution.

product_ids = ProductClick.where(user_id: user.id).order('count desc').pluck(:product_id)

products = Product.where(id: product_ids)

It'll definitely improve your time and is better than your query (which is N+1).

Using preloading

Product.includes(:product_clicks).where('product_clicks.user_id' => user.id).order('product_clicks.count desc')

The above query should also result in the same way, however, it may internally hit 2 queries anyway.

Using having clause - Recommended

Product.includes(:product_clicks).having('product_clicks.user_id' => user.id).order('product_clicks.count desc')

Update - Using OR

Product.includes(:product_clicks).where('product_clicks.user_id' => user.id)
       .order('product_clicks.count desc')
       .or(
        Product.includes(:product_clicks)
               .where('product_clicks.user_id' => user.id)
               .where(product_clicks: { id: nil })
       )