在MySQL中选择两个列表和？

Question

我可以用SUM()功能在MySQL方便地选择一列的总和，像这样：

SELECT SUM(`someColumn`) FROM `table` 

是否也可以用相同的查询返回第二列的总和？与此相似：

SELECT SUM (`someColumn`, `anotherColumn`) FROM `table` 

运行这样的查询返回我下面的访问冲突：

SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' `anotherColumn`) FROM `table`' at line 1 

Answer 1

尝试用：

SELECT SUM(COALESCE(`someColumn`, 0)+ COALESCE(`anotherColumn`, 0)) as TotalSum FROM `table` 

，或者如果你这些单独想：

SELECT SUM(`someColumn`) as Sum1, SUM(`anotherColumn`) as Sum2 FROM `table` 

Answer 2

SELECT SUM(`someColumn`) + SUM(`anotherColumn`) as TotalSum FROM `table` 

Answer 3

一个更简单的方法：

SELECT col1, col2, col3, (col1+col2+col3) AS Total FROM table; 

Answer 4

如果要总结多个列，您只需选择多列的总和。

如果你只想要总列，你可以这样做：

SELECT SUM(col1+col2+...+coln) AS all_total 

如果你想保留的款项分开，你可以这样做：

SELECT SUM(col1) AS total1, SUM(col2) AS total2, ..., SUM(coln) AS totaln