带有 SUM(CASE SUBQUERY) 的子查询聚合函数

Question

我在执行查询时遇到错误

Cannot perform an aggregate function on an expression containing an aggregate or a subquery.

代码：

SELECT 
    S.id,
    SUM(CASE WHEN sc.coverage IN (SELECT number FROM ArrayOfIntegersFromString(@dynamicData)) THEN 1 ELSE 0 END) as sm
FROM 
    Storefronts s
    LEFT JOIN StorefrontCoverages sc ON s.id = sc.storefront
    LEFT JOIN Vendors v ON s.vendor = v.Id
WHERE
(
    v.active = 1
    AND
    s.approved = 1
    AND
    s.status = 1 
)
GROUP BY S.id
HAVING SUM(CASE WHEN sc.coverage IN (SELECT number FROM ArrayOfIntegersFromString(@dynamicData)) THEN 1 ELSE 0 END)  > 0
ORDER BY sm desc

SELECT 中的

SUM 不如 HAVING 中的重要] 会有帮助。

Answer 1

我认为将子查询移至from 子句会更好。根据您的逻辑，您正在寻找 join，而不是 left join——毕竟，having 子句只是在寻找任何匹配项。

我认为以下查询可以满足您的要求：

SELECT S.id, COUNT(dd.number) as sm
FROM Storefronts s JOIN
     StorefrontCoverages sc
     ON s.id = sc.storefront JOIN
     (SELECT number FROM ArrayOfIntegersFromString(@dynamicData)
     ) dd(number)
     ON sc.coverage = dd.number
WHERE s.approved = 1 AND s.status = 1 AND
      EXISTS (SELECT 1
              FROM Vendors v
              WHERE s.vendor = v.Id AND
                    v.active = 1
             )
GROUP BY S.id
ORDER BY sm desc;

带有 SUM(CASE SUBQUERY) 的子查询聚合函数

Subquery aggregate function with SUM(CASE SUBQUERY)

sql

sql-server

sum

subquery

aggregate-functions