将数据表的结果集转换为多列

Question

表@Table1包含结果集，需要将其转换为下面提到的Output格式。

        DECLARE @Table1 TABLE
            (
              DomainID INT ,
              AttributeName VARCHAR(20) ,
              UOM VARCHAR(10) ,
              Quantity DECIMAL(14, 2)
            );

        INSERT  INTO @Table1
                ( DomainID, AttributeName, UOM, Quantity )
        VALUES  ( 1, 'CPU_Usage', 'RPM', 19.86 ),
                ( 1, 'Bandwidth', 'kbps', 68820.00 ),
                ( 1, 'Storage', 'Mb', 116.63 ),
                ( 2, 'CPU_Usage', 'RPM', 27.46 ),
                ( 2, 'Bandwidth', 'kbps', 79970.00 ),
                ( 2, 'Storage', 'Mb', 157.05 ),
                ( 3, 'CPU_Usage', 'RPM', 3.27 ),
                ( 3, 'Bandwidth', 'kbps', 5924.00 ),
                ( 3, 'Storage', 'Mb', 96.66 );
        SELECT  *
        FROM    @Table1;

需要转动的表格数据。

        DomainID    AttributeName   UOM     Quantity
        1           CPU_Usage       RPM     19.86
        1           Bandwidth       kbps    68820.00
        1           Storage         Mb      116.63
        2           CPU_Usage       RPM     27.46
        2           Bandwidth       kbps    79970.00
        2           Storage         Mb      157.05
        3           CPU Usage       RPM     3.27
        3           Bandwidth       kbps    5924.00
        3           Storage         Mb      96.66
        3           Storage         Mb      96.66

必填Output

Answer 1

调用条件聚合进行救援：

DECLARE @Table1 TABLE
    (
        DomainID INT ,
        AttributeName VARCHAR(20) ,
        UOM VARCHAR(10) ,
        Quantity DECIMAL(14, 2)
    );

INSERT  INTO @Table1
        ( DomainID, AttributeName, UOM, Quantity )
VALUES  ( 1, 'CPU_Usage', 'RPM', 19.86 ),
        ( 1, 'Bandwidth', 'kbps', 68820.00 ),
        ( 1, 'Storage', 'Mb', 116.63 ),
        ( 2, 'CPU_Usage', 'RPM', 27.46 ),
        ( 2, 'Bandwidth', 'kbps', 79970.00 ),
        ( 2, 'Storage', 'Mb', 157.05 ),
        ( 3, 'CPU_Usage', 'RPM', 3.27 ),
        ( 3, 'Bandwidth', 'kbps', 5924.00 ),
        ( 3, 'Storage', 'Mb', 96.66 );

SELECT  DomainID
      , MAX(CASE WHEN AttributeName='CPU_Usage' THEN UOM END) AS CPU_UOM
      , MAX(CASE WHEN AttributeName='CPU_Usage' THEN Quantity END) AS CPUQuantity
      , MAX(CASE WHEN AttributeName='Bandwidth' THEN UOM END) AS Bandwidth_UOM
      , MAX(CASE WHEN AttributeName='Bandwidth' THEN Quantity END) AS BandwidthQuantity
      , MAX(CASE WHEN AttributeName='Storage' THEN UOM END) AS Storage_UOM
      , MAX(CASE WHEN AttributeName='Storage' THEN Quantity END) AS StorageQuantity
FROM    @Table1
GROUP BY DomainID;

Answer 2

        SELECT  PivotTable.DomainID ,
                PivotTable.[CPU_Usage(RPM)] ,
                PivotTable.[Bandwidth(kbps)] ,
                PivotTable.[Storage(Mb)]
        FROM    ( SELECT    DomainID ,
                            AttributeName + '(' + UOM + ')' AS Attribute ,
                            Quantity
                  FROM      @Table1
                ) src PIVOT
        ( MAX(Quantity) FOR Attribute IN ( [CPU_Usage(RPM)], [Bandwidth(kbps)],
                                           [Storage(Mb)] ) ) PivotTable;