语法错误辅助

Question

我的语法有什么问题？

select sum(a.total) from (
sum(`PCPrice` * TaxVariable) AS PCPriceTotal,
(select count(*)  from DBname where PCPriceTotal > 0 ) as total
from DBname group by PCPriceTotal) as a

  

您的SQL语法有错误;查看与您的MySQL服务器版本对应的手册，以便在'sum（PCPrice * TaxVariable）AS PCPriceTotal附近使用正确的语法，（从第2行的DBname'中选择count（*）

解决。简单的错误。错过了“选择”。修正：

select sum(a.total) from (
select sum(`PCPrice` * TaxVariable) AS PCPriceTotal,
(select count(*)  from DBname where PCPriceTotal > 0 ) as total
from DBname group by PCPriceTotal) as a

Answer 1

您忘记在您的子查询中加上'SELECT'，它位于SUM(`PCPrice` * TaxVariable) AS PCPriceTotal之前。

SELECT SUM(a.total) FROM 
(SELECT
    SUM(`PCPrice` * TaxVariable) AS PCPriceTotal,
    (SELECT COUNT(*)  FROM DBname WHERE PCPriceTotal > 0 ) AS total
    FROM DBname GROUP BY PCPriceTotal
) AS a

Answer 2

您正在使用函数代替表（sum（PCPrice * TaxVariable）AS PCPriceTotal ，

你的要求是什么。