Ms Ms计算来自多行

Question

我有以下查询：

SELECT 
    InspectionID, Distance, Continuous, structural_grade  
FROM 
    Conditions
WHERE 
    Continuous LIKE ("S%") OR Continuous LIKE ("F%")
ORDER BY 
    InspectionId ASC, Distance ASC

哪个输出：

262 60.80   S01 3
262 73.10   F01 3
262 82.60   S02 2
262 140.30  F02 2
263 30.80   S01 2
263 46.60   F01 2
380 4.60    S01 3
380 8.50    F01 3
380 9.80    S02 4
380 28.20   F02 4
380 77.70   S03 4
380 97.70   F03 4

订购是正确的。但是，我仍然坚持下一步该做什么。

每个＆＃34; S＆＃34;有一个匹配的＆＃34; F＆＃34;使用相同的编号Ex S01，F01。我需要访问每个＆＃34; F＆＃34;的距离字段。和减去＆＃34; S＆＃34;与它的距离。

例如，F01的距离为73.10，S01为60.80，因此距离为12.3。我需要为每个记录执行此操作，并在＆＃34; S＆＃34;之后编号。和＆＃34; F＆＃34;可以真的很高但总会匹配。恩。 S999 - F999

Answer 1

使用Mid()功能从Continuous字段中提取数字：Mid("S01", 2)产生“01”。然后在加入 F 和 S 行时使用这些数字。

使用Access 2010中的示例数据，以下查询为我提供了此结果集：

SELECT
    f.InspectionID,
    f.Continuous,
    s.Continuous,
    f.Distance AS F_distance,
    s.Distance AS S_distance,
    f.Distance - s.Distance AS F_minus_S
FROM
    Conditions AS f
    INNER JOIN
        (
            SELECT
                InspectionID,
                Continuous,
                Distance,
                Mid([Continuous],2) AS digits_only
            FROM Conditions
            WHERE Continuous ALike 'S%'
        ) AS s
    ON
            f.InspectionID = s.InspectionID
        AND Mid(f.[Continuous],2) = s.digits_only
WHERE f.Continuous ALike 'F%'
ORDER BY f.InspectionId ASC, f.Distance ASC;

我在最终查询中包含了几个我怀疑你想要的列。但我认为它们在开发和测试过程中非常有用。

请注意Access查询设计器会抱怨它无法在设计视图中表示该连接条件。如果在 SQL View 中设置连接，则可以在没有Access抱怨的情况下运行查询。

Answer 2

SELECT a.continuous AS 'S Continuous',
a.distance AS 'S Distance',
b.continuous AS 'F Continuous',
b.distance AS 'F Distance',
abs(a.distance - b.distance) AS 'Difference'

FROM Conditions a

INNER JOIN Conditions b
ON a.InspectionID = b.InspectionID
AND substring(a.continuous,2,len(a.continuous)-1) = substring(b.continuous,2,len(b.continuous)-1)

WHERE a.Continuous LIKE 'S%'
AND b.Continuous LIKE 'F%'

ORDER BY a.InspectionId ASC, a.Distance ASC