如何在SQL中合并两行时将一列拆分为两列？

Question

请参阅下表。

Sr.No  Field1     Field2       Field3
----------------------------------
1.      ABC       abc@abc       HTML
2.      ABC       efg@efg       XML

必需的输出：

Sr.No   Field1      HTML          XML
--------------------------------------
1.       ABC       abc@abc       efg@efg

感谢。

Answer 1

你可以这样做吗

DECLARE @T TABLE
(
    SeqNo INT IDENTITY(1,1),
    Col1 NVARCHAR(255),
    Col2 NVARCHAR(255),
    Col3 NVARCHAR(255)
)

INSERT INTO @T
(
    Col1,
    Col2,
    Col3
)
VALUES('ABC','abc@abc','HTML'),
       ('ABC','efg@efg','XML')


SELECT
    T1.SeqNo,
    T1.Col1,
    HTML = T1.Col2,
    [XML] = T2.Col2
    FROM @T T1
       LEFT JOIN @T T2
          ON T1.Col1 = T2.Col1
             AND T2.Col3 = 'XML'
    WHERE T1.Col3 = 'HTML' 

或使用PIVOT像这样

SELECT
    SeqNo = MIN(SeqNo),
    Col1 = Col1,
    HTML = MAX(Html),
    [xml] = MAX([XML])
    FROM @T
    PIVOT
    (
       MAX(Col2)
       FOR
       COL3
       IN
       (
          [HTML],[XML]
       )  
     )Q  
     GROUP BY Col1

但我认为第一个解决方案应该有效

输出

Answer 2

SELECT `T1`.`Sr.No`, `T1`.`Field1`, `T1`.`Field2` AS HTML, 
(SELECT `T2`.`Field2` AS XML FROM TABLE_NAME T2 
WHERE `T2`.`Field3` = 'XML' AND `T2`.`Field1` = `T1`.`Field1`) 
FROM TABLE_NAME T1 WHERE `T1`.`Field3` = 'HTML'