I'm looking to create a user system with a basic profile system. I want users to be able to input and edit a field. Then I want to display the total change in that field for all users on a certain part of the page.

How would I do this?

For example:

user 1
20 apples
edit: 10 apples
change: 10 apples

user 2:
10 apples
edit: 5 apples
change: 5 apples

user 3:
2 apples
edit: 0 apples
change: 2 apples

Total Change: Change user 1 + change user 2 + change user 3 = 10+5+2 = 17

I would want that value of 17 displayed on the page somewhere. How would I implement such a system?

If you have already read the jquery.com library tutorials, it may help you on this issue. You may use for example $.post ajax call to post value from front end. And edit in place and to display the computation then and there.

I was under the impression this can be done purely with PHP and a MySQL database

Originally Posted by andrei155

I was under the impression this can be done purely with PHP and a MySQL database

If you don't mind doing page refreshing then you can implement it using php and mysql only.
But displaying total value without refreshing the page will require you some javascript coding at minimal.

Using jQuery will simplify that process and will help you overcome incompatibility issues with browsers without need to know each browser specifications.

If I use jQuery will I still be using a MySQL DB? Would anyone mind pointing me in the right direction?

Originally Posted by andrei155

If I use jQuery will I still be using a MySQL DB? Would anyone mind pointing me in the right direction?

You need to store that information permanently right? then you need either to use files or db to store permanent information

jQuery is just a way for making site responsive without need to press submit button or refresh the page. like dynamically changing information in the page.
check this page for some info about jquery
http://docs.jquery.com/How_jQuery_Works

Since you don't know about jQuery yet, my suggestion is to make it using static html then if you like you can change it later to use jQuery.