rails 4 how to use where and where in condition simultaneously

Question

I have the following query

model = (1,2,3,4)
@posts = Post.where(category_id: id,  product_model_id: model)

My above query is justing taking the 1 from model how can i use where in condition over here

Edit-1

This piece of code works but I don't feel this as a good code right?

@posts = Post.where("category_id = ? and product_model_id in (#{model})", id)

Edit-2

If I use

@posts = Post.where("category_id = ? and product_model_id in (?)", id, model)

Throwing error as

invalid input syntax for integer: "15,16" because my input is like this

select * from posts where category_id=5 and product_model_id in ('15,16')

How to correct it then..

Answer 1

model_ids = model.split(",").map(&:to_i)
@posts = Post.where(category_id: id, product_model_id: model_ids)

or

model_ids = model.split(",").map(&:to_i)
@posts = Post.where("category_id = ? AND product_model_id IN (?)", id, model_ids)