Question

查询1：

    SELECT DISTINCT FirstOfFrequencyMHz, Min(LicenceData.distance) AS CoFX
FROM [Freq List], LicenceData
WHERE ((([LicenceData].class_stat) Like 'F*') And (([LicenceData].type_lc)="A") And (([LicenceData].frequency) Between FirstOfFrequencyMHz-0.0249 And FirstOfFrequencyMHz+0.0249))
GROUP BY FirstOfFrequencyMHz

QUERY2：

    SELECT DISTINCT FirstOfFrequencyMHz, Min(LicenceData.distance) AS CoMO
FROM [Freq List], LicenceData
WHERE ((([LicenceData].class_stat) Like 'M*') And (([LicenceData].type_lc)="A") And (([LicenceData].frequency) Between FirstOfFrequencyMHz-0.0249 And FirstOfFrequencyMHz+0.0249))
GROUP BY FirstOfFrequencyMHz

综合查询尝试：

SELECT DISTINCT FirstOfFrequencyMHz, 

(SELECT Min(distance) AS Expr1
FROM [Freq List], LicenceData
WHERE ((([LicenceData].class_stat) Like 'F*') And (([LicenceData].type_lc)="A") And (([LicenceData].frequency) Between FirstOfFrequencyMHz-0.0249 And FirstOfFrequencyMHz+0.0249))) as COFX,

(SELECT Min(distance) AS Expr1
FROM [Freq List], LicenceData
WHERE ((([LicenceData].class_stat) Like 'M*') And (([LicenceData].type_lc)="A") And (([LicenceData].frequency) Between FirstOfFrequencyMHz-0.0249 And FirstOfFrequencyMHz+0.0249))) as COMO

FROM [Freq List]

我发布的合并查询尝试未返回正确的值，CoFX和CoMO列的所有单元格都包含相同的数字。

这两个查询独立工作我只需要知道如何组合它们（我需要组合4个总查询，类似于前2个发布的查询）或者甚至可以将它们组合起来。

Answer 1

这可能是最好的方法，因为表之间没有直接链接，您需要使用子选择以确保它们被正确引用：

SELECT DISTINCT F.FirstOfFrequencyMHz,
(
SELECT Min(L.Distance)
FROM LicenceData As L
WHERE L.Class_Stat Like 'F*'
AND L.Type_LC = 'A'
AND L.Frequency Between F.FirstOfFrequencyMHz-0.0249 And F.FirstOfFrequency+0.0249
) CoFX,
(
SELECT Min(L2.Distance)
FROM LicenceData As L2
WHERE L2.Class_Stat Like 'M*'
AND L2.Type_LC = 'A'
AND L2.Frequency Between F.FirstOfFrequencyMHz-0.0249 And F.FirstOfFrequency+0.0249
) CoMO
FROM [Freq List] As F

祝你好运：）

如何将这两个查询合并为一个？

1 个答案: