Làm cách nào để kết hợp dữ liệu từ nhiều hàng thành một?

Sử dụng PIVOT Bạn có thể làm như sau

With SampleData AS 
(
SELECT 'Team1' as Team , 'example@sqldat.com' as email, 'A' as Groups
UNION SELECT 'Team1' as Team , 'example@sqldat.com' as email, 'B' as Groups
UNION SELECT 'Team1' as Team , 'example@sqldat.com' as email, 'C' as Groups
UNION SELECT 'Team2' as Team , 'example@sqldat.com' as email, 'A' as Groups
UNION SELECT 'Team2' as Team , 'example@sqldat.com' as email, 'B' as Groups
UNION SELECT 'Team2' as Team , 'example@sqldat.com' as email, 'C' as Groups
)
SELECT Team, A, B,C FROM 
(SELECT * FROM SampleData) source
PIVOT
(MAX(email) FOR Groups IN ([A], [B], [C]) )as pvt

Sản xuất

Team  A                B                C
----- ---------------- ---------------- ----------------
Team1 example@sqldat.com example@sqldat.com example@sqldat.com
Team2 example@sqldat.com example@sqldat.com example@sqldat.com

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Trong một DB không hỗ trợ PIVOT, thay vào đó, bạn có thể thực hiện nhiều phép nối vào bảng của mình. Mặc dù bạn có thể muốn, nhưng như GBN đã chỉ ra, vì chúng tôi không sử dụng tổng hợp.

With SampleData AS 
(
SELECT 'Team1' as Team , 'example@sqldat.com' as email, 'A' as Groups
UNION SELECT 'Team1' as Team , 'example@sqldat.com' as email, 'B' as Groups
UNION SELECT 'Team1' as Team , 'example@sqldat.com' as email, 'C' as Groups
UNION SELECT 'Team2' as Team , 'example@sqldat.com' as email, 'A' as Groups
UNION SELECT 'Team2' as Team , 'example@sqldat.com' as email, 'B' as Groups
UNION SELECT 'Team2' as Team , 'example@sqldat.com' as email, 'C' as Groups
)

SELECT 
    source.Team,
    A.email,
    B.email,
    C.email
FROM 
    (SELECT DISTINCT TEAM From SampleData) source
    LEFT JOIN SampleData A 
    ON source.Team = A.Team
     AND A.GROUPS = 'A'
    LEFT JOIN SampleData B 
    ON source.Team = B.Team
    AND B.GROUPS = 'B'
    LEFT JOIN SampleData C 
    ON source.Team = C.Team
    AND C.GROUPS = 'C'

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