SQL如果语法错误

Question

我有lil - 一个sql卡错误（1064）。

SELECT sum(if(d.o_amount<='10')) as ten_s

我知道我们这里有简单的语法错误，但我怎么能解决它？ 感谢名单！

Answer 1

我想你的意思是：

SELECT sum(d.o_amount) as ten_s FROM table_name WHERE d.o_amount <= 10

Answer 2

使用CASE

SELECT SUM(CASE WHEN d.o_amount<=10 THEN d.o_amount ELSE 0 END) as ten_s

Answer 3

即使您可以使用CASE表达式。只是另一种观点。

<强>查询

select sum(case when d.o_amount <= 10 then d.o_amount else 0 end) as ten_s
from your_table_name;

Answer 4

根据您的查询的其余部分：

您可以在金额值上添加限制：

SELECT sum(d.o_amount) as ten_s 
FROM table_name 
WHERE d.o_amount <= 10

或者使用case表达式来保留所有行，但只需要总和：

SELECT sum(case when d.o_amount <= 10 then d.o_amount else 0 end) as ten_s