如何通过PHP从MySQL数据库中的两个不同行计算两个不同值

Question

Actually I am creating database on wamp server with the help of php. There is some calculation among some fields.This database for is for lab procurement in which every entry is for new file.Every thing is done but the problem is come when I try to insert a new values for a new file but one value is depend on a value of a previous file. like A(FILE NO) BCD 1 2 3 4 2 5 5 9(D1+C2)

So how does is it possible? I am new to this language so if there is another way to do this then please tell me.

Answer 1

You really should use HeidiSQL to create and manage your database, it's much easier.Then you just create a link in php with a php file. As for your question ,yes it is possible quite easy actually :

$id=0;//a counter to determine if you had inserted an item
if(isset($_POST['some_item'])){// when a value is set, like adding a new item to your database using the post method
   INSERT....//whatever you want
   $id=$_POST['id'];//the id of the item you just inserted ,which is also the counter
}
if($id!=0)
   //execute whatever code you want