Question

我在mySQL表中有多个列。其中三列被命名为i100s，i60s和i25s，我想要做的就是得到所有三个条目的总和。目前我有这个代码

   '$query= "SELECT SUM(i100s),SUM(i60s),SUM(i25s) AS tkit FROM event WHERE acc='100' " ; 
    $result = mysql_query($query) or die(mysql_error());
    $row = mysql_fetch_assoc($result) ;
    $total =  $row['tkit'];'

但它没有返回正确的结果。

Answer 1

所有三列的总和？

如果是这样，只需将它们添加起来：

'$query= "SELECT SUM(i100s) + SUM(i60s) + SUM(i25s) AS tkit FROM event WHERE acc='100' " ;

Answer 2

SELECT (SUM(i100s) + SUM(i60s) + SUM(i25s)) AS tkit ...

这将返回列总和的总和。

Answer 3

将有不同的方法....付款是在method_1，method_2，method_3上支付的。所以我想计算一个特定方法的总和，比如1000 ..对于所有方法类型。

表：payment_test

id method_1 payment_1 method_2 payment_2 method_3 payment_3
1  1000     100       1001     200       1001     100
2  1011     100       1000     100       1000     100
3  1010     200       1001     100       1010     200
4  1000     400       1010     500       1001     100


SELECT SUM(
    CASE WHEN method_1 ='1000' THEN payment_1 ELSE 0 END
    + CASE WHEN method_2 ='1000' THEN payment_2 ELSE 0 END
    + CASE WHEN method_3 ='1000' THEN payment_3 ELSE 0 END) as payment
FROM payment_test

输出：

付款
700

MySQL查询，多列的SUM

3 个答案: