[当有几个属性时通过sql查询从xml中获取值

Question

有带有几个属性“ Num”的xml

DECLARE @XML XML = '
<FileId global_id="1234">
  <file id="12aa">
  </file>
  <file id="12bb">
    <Number Num = "1"/>
    <Number Num = "2"/>
  </file>
</FileId>';

使用此sql查询只能获得一个属性

SELECT F.[File].value(N'../@global_id','varchar(100)') as id_payment,
  F.[File].value('@id', 'varchar(4)') AS id,
  F.[File].value('(Number/@Num)[1]', 'int') as [Num]
FROM (VALUES (@XML)) V (X)
  CROSS APPLY V.X.nodes('/FileId/file') F([File]) 

如何获取所有属性-Num = 1和Num = 2。可以是可变数量的属性。

id_payment  id      Num
1234        12aa    NULL
1234        12bb    1
1234        12bb    2

Answer 1

DECLARE @XML XML = '
<FileId global_id="1234">
  <file id="12aa">
  </file>
  <file id="12bb">
    <Number Num = "1"/>
    <Number Num = "2"/>
    <Number Num = "3"/>
    <Number Num = "4"/>
    <Number Num = "5"/>
    <Number Num = "6"/>
  </file>
</FileId>';



SELECT F.[File].value(N'../@global_id','varchar(100)') as id_payment,
  F.[File].value('@id', 'varchar(4)') AS id,
  F.[File].value('(Number/@Num)[1]', 'int') as [Num],
  n.num.value('(@Num)[1]', 'int') as [Numxyz]

FROM (VALUES (@XML)) V (X)
  CROSS APPLY V.X.nodes('/FileId/file') F([File]) 
  outer apply F.[File].nodes('Number') as n(num)

Answer 2

更简单的版本。无需使用VALUES子句。 OUTER APPLY模拟LEFT OUTER JOIN。