Question

我有表1.我希望输出如表2所示请帮帮我

Table 1
Student_ID AttCode AttDate
101        AE      1-1-2011
101        H       1-2-2011
101        T       1-5-2011
101        H       1-7-2011
101        AU      1-8-2011
102        AE      1-1-2011
102        AE      1-3-2011
102        H       1-4-2011
102        V       1-5-2011

Table 2
Student_ID FromDate  To date   ConsecutiveAbs AttCodes
101        1-1-2011  1-2-2011  2              AE,H
101        1-5-2011  1-8-2011  4              T,AE,H,AU
102        1-1-2011  1-1-2011  1              AE
102        1-3-2011  1-5-2011  2              AE,H,V

Answer 1

你走了！完整的脚本，只需确保对每种可能的情况都进行测试，如果符合您的需要，请不要忘记将其标记为答案：

IF OBJECT_ID('TEST1') IS NOT NULL
DROP TABLE TEST1
GO
CREATE TABLE TEST1
(
STUDENTID INT ,
ATTCODE VARCHAR(2) ,
ATTDATE DATE
)
GO
INSERT INTO TEST1
VALUES 
('101','AE','20110101'),
('101','H','20110102'),
('101','T','20110105'),
('101','H','20110107'),
('101','AU','20110108'),
('102','AE','20110101'),
('102','AE','20110103'),
('102','H','20110104'),
('102','V','20110105')
GO

IF OBJECT_ID('TEST2') IS NOT NULL
DROP TABLE TEST2
GO

CREATE TABLE TEST2
(
STUDENTID INT,
FROMDATE DATE,
TODATE DATE,
CONSECUTIVEABS INT,
ATTCODES VARCHAR(255)
)
GO

INSERT INTO TEST2
SELECT TEST1.STUDENTID,TEST1.ATTDATE,TEST1.ATTDATE,1,TEST1.ATTCODE
FROM TEST1
JOIN 
    (
    SELECT STUDENTID,MIN(ATTDATE) ATTDATE
    FROM TEST1
    GROUP BY STUDENTID
    ) MI ON MI.STUDENTID=TEST1.STUDENTID AND MI.ATTDATE=TEST1.ATTDATE

DECLARE @STUDENTID INT, @ATTCODE VARCHAR(2), @ATTDATE DATE

DECLARE CRS CURSOR LOCAL FAST_FORWARD FOR
SELECT TEST1.STUDENTID,TEST1.ATTCODE,TEST1.ATTDATE
FROM TEST1
LEFT JOIN TEST2 ON TEST1.STUDENTID=TEST2.STUDENTID AND TEST1.ATTCODE=TEST2.ATTCODES AND TEST1.ATTDATE=TEST2.FROMDATE
WHERE TEST2.STUDENTID IS NULL
ORDER BY 1,3 ASC

OPEN CRS

FETCH NEXT FROM CRS INTO @STUDENTID, @ATTCODE, @ATTDATE

WHILE @@FETCH_STATUS=0
BEGIN

    IF EXISTS 
    (
    SELECT 1 
    FROM TEST2
    WHERE STUDENTID=@STUDENTID AND DATEADD(DD,1,TODATE)=@ATTDATE
    )
        UPDATE TEST2
        SET TODATE=@ATTDATE, ATTCODES+=','+@ATTCODE, CONSECUTIVEABS+=1
        WHERE STUDENTID=@STUDENTID AND DATEADD(DD,1,TODATE)=@ATTDATE
    ELSE 
        INSERT INTO TEST2
        SELECT @STUDENTID,@ATTDATE,@ATTDATE,1,@ATTCODE


    FETCH NEXT FROM CRS INTO @STUDENTID, @ATTCODE, @ATTDATE
END


SELECT * FROM TEST2
ORDER BY 1,2

它没有处理的一种情况是你在输入表中有相同的studenId和attdate以及不同的attcode。你没有提到任何关于这种情况的事情，这就是为什么它不是由上面的代码处理的。

如何在一行的单个单元格中使用逗号合并多个单元格值，但有一些限制

1 个答案: