Rails where In doesn't recognise where

Question

I keep getting an error undefined method where when running the code below with these parameters.

Can anyone see what I'm doing wrong?

Thanks

 Parameters: {"category_ids"=>["1", "3", "4"]}

    @pieces = Piece.all
    @pieces = @pieces.where(:category_id => params[:category_ids]) if params[:category_ids].present?
    @pieces = @pieces.where(:brand_id => params[:brand_ids]) if params[:brand_ids].present?
    @pieces = @pieces.where(:color_id => params[:color_ids]) if params[:color_ids].present?
    @pieces = @pieces.where(:user_id => params[:friend_ids]) if params[:friend_ids].present?

Answer 1

It should be:

Piece.where(:category_id => params[:category_ids]) if params[:category_ids].present?