sql - 在 where 子句中使用“AND”时出现错误“参数必须是布尔类型”

Question

错误：AND 的参数必须是布尔类型，而不是类型字符变化

SELECT 
    partno, 
    count(manufacturer) 
FROM 
    components 
WHERE 
    partno IN (SELECT partno FROM productions 
               WHERE 
                    year = 2005
                AND attr is NULL
              ) 
GROUP BY partno
UNION
SELECT 
    partno, 
    count(manufacturer) 
FROM components 
WHERE 
    partno IN (SELECT partno FROM productions 
               WHERE 
                   year = 2005
               AND attr is NULL
              ) 
GROUP BY partno
) 
AND (
        partno NOT IN (SELECT partno FROM components
    )
); 

union 之后的部分是包含所有不在生产中的组件的 partno（它们应该计为 0）

Answer 1

您有一个括号太多（在 之后attr IS NULL），并且您有一个聚合函数（count在第二部分中）而没有group by. 你是这个意思吗：

select partno, count(manufacturer) 
from components 
where partno in 
(
   select partno from productions where year=2005 and attr is NULL
) 
group by partno

UNION

select partno, count(manufacturer) 
from components 
where partno in 
(
    select partno from productions where year=2005 and attr is NULL
) 
AND partno not in (select partno from components)
group by partno;