Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I have two entity groups. Restaurants and Users. Restaurants can be rated (1-5) by users. And rating fromeach user should be retrievable.
Resturant(id, name, ….. , total_number_of_votes, total_voting_points )
User (id, name …… )
Rating (id, restaurant_id, user_id, rating_value)
Do i need to store the avg value so that it need not be calculated every time ? which table is the best place to store avg_rating, total_no_of_votes, total_voting_points ?
Well, if you store the average value somewhere; it will only be accurate as of the last time you calculated it. (i.e. you have 5 reviews; then store the averages somewhere. You get 5 more new reviews, and then your saved average is incorrect).
My opinion is that this sort of logic is perfectly suited to a middle-tier. Calculating an average shouldn’t be very resource intensive, and really shouldn’t impact performance.
If you really want to store it in the database; I would probably store them in their own table, and update those values via triggers. However, this could be even more resource intensive than calculating it in the middle-tier.