Rating Calculate formula?

[somwang]

Dear all experts

im now creating a rating system with php using mysql databse,
im facing the problem about how to calculate rating!, ex. i have totalscore and numofvotes table, which function that we can use to calculate rating like, 7.4, 4.5 something like that

thanks in advance

[darkagn]

You are probably better off having a single table in your database that just contains the votes of each user on each item being rated. This way you can ensure that each voter can only vote once for something. In order to calculate the total score, number of votes and average rating, you can do this:

SELECT SUM(Votes), COUNT(Votes), AVG(Votes) FROM UserVotes
WHERE Item = Whatever

or something similar...

[Shanti C]

AVG(Votes) is exactly what you want......

[maringtr]

Hey, I just posted an article on my blog that explains the correct approach to do this: http://www.marinbezhanov.com/web-development/18/calculating-average-rating-the-right-way-using-php-and-mysql/

I think you'll find it useful..