如果发生新条目，则更新或更改整个列值

Question

id  name    amt    %
1    A     3000   100%
2    B     1500   45%

现在我有SUM(amount)*A(amount)/100的总和，我得到了100％作为A＆＃39的贡献 现在，如果我们有另一个伙伴输入第二个值，它将计算新总值的百分比，但我希望旧值（即100％）也应该重新计算，因为总数现在增加了。就像我明智的那样，我有很多行。它应该以新的总数来计算。

我被困在这里，使用php。

代码：

$result = mysql_query("SELECT SUM(amount) AS val_sum FROM member_detail") or die(mysql_error());
$row = mysql_fetch_assoc($result); 
$sum = $row['val_sum']; 
$sumall = $sum+$amount; 
//echo ($sumall); 
$avg = $amount/$sumall*100; 
$sql = "insert into investment (mem_name,p_amount,percentage) values ('$name','$amount','$avg')"; 
$query = mysql_query($sql) or die(mysql_error()); 
$obj->insert("member_detail",$_POST); 
$msg = "Member added Successfully";

Answer 1

试试这段代码

<?php
$obj->insert("member_detail",$_POST); 

$result = mysql_query("SELECT SUM(amount) AS val_sum FROM member_detail")or die(mysql_error());
$row = mysql_fetch_assoc($result); 
$sum = $row['val_sum'];

$sql = "insert into investment (mem_name,p_amount,percentage) values ('$name','$amount',0)"; 
$query = mysql_query($sql) or die(mysql_error());
$result = mysql_query("SELECT id AS val_sum FROM member_detail")or die(mysql_error());
while($row = mysql_fetch_assoc($result)){
$sumall = $row['val_sum']; 
$avg = $amount/$sumall*100; 
$sql = "update investment set percentage='$avg' where id=".$row['id']; 
$query = mysql_query($sql) or die(mysql_error()); 
}
$msg = "Member added Successfully";