在 SQL Server 中解析 XML 的问题

Question

我是在 SQL Server 中处理 XML 数据的新手。我遇到了一篇文章 (https://www.mssqltips.com/sqlservertip/2899/importing-and-processing-data-from-xml-files-into-sql-server-tables/) 并尝试根据我的 XML 进行修改，但我没有得到任何输出或错误。我不知道如何进一步进行，任何帮助表示赞赏。我提供了以下示例：

    DECLARE @XML AS XML, @hDoc AS INT, @SQL NVARCHAR (MAX)

SELECT @XML = '<DataSet xmlns="http://www.example.com/">
  <diffgr:diffgram xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1">
    <NewDataSet xmlns="">
      <General_x0020_Report diffgr:id="General Report1" msdata:rowOrder="0">
        <Device_x0020_No>224610</Device_x0020_No>
        <License_x0020_Plate>AAA 123</License_x0020_Plate>
        <Driver>Driver Name</Driver>
        <Date_x002F_Time>2018-01-01T12:46:04+03:00</Date_x002F_Time>
      </General_x0020_Report>
     </NewDataSet>
  </diffgr:diffgram>
</DataSet>'

EXEC sp_xml_preparedocument @hDoc OUTPUT, @XML


SELECT Device_x0020_No, License_x0020_Plate, Driver, Date_x002F_Time
FROM OPENXML(@hDoc, 'DataSet/diffgr/NewDataSet/General_x0020_Report')
WITH 
(
Device_x0020_No [varchar](50) 'Device_x0020_No',
License_x0020_Plate [varchar](100) 'License_x0020_Plate',
Driver [varchar](100) 'Driver',
Date_x002F_Time [varchar](100) 'Date_x002F_Time'
)


EXEC sp_xml_removedocument @hDoc
GO

编辑 1：我发现问题在于“diffgr:diffgram”，但不确定如何解决此查询中的命名空间问题

Answer 1

FROM OPENXML 与相应的 SP 准备和删除文档已过时，不应再使用。而是使用适当的methods the XML data type provides。

您的 XML 在第一行定义默认命名空间，并使用 <NewDataSet> 将默认命名空间重新定义为空。这意味着，所有在<NewDataSet> 下的节点都不存在于任何命名空间中。

DECLARE @XML AS XML, @hDoc AS INT, @SQL NVARCHAR (MAX)

SELECT @XML = '<DataSet xmlns="http://www.example.com/">
  <diffgr:diffgram xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1">
    <NewDataSet xmlns="">
      <General_x0020_Report diffgr:id="General Report1" msdata:rowOrder="0">
        <Device_x0020_No>224610</Device_x0020_No>
        <License_x0020_Plate>AAA 123</License_x0020_Plate>
        <Driver>Driver Name</Driver>
        <Date_x002F_Time>2018-01-01T12:46:04+03:00</Date_x002F_Time>
      </General_x0020_Report>
     </NewDataSet>
  </diffgr:diffgram>
</DataSet>';

--简单的方法是使用// 进行深度搜索，直接跳转到感兴趣的节点：

SELECT @XML.value(N'(//Device_x0020_No)[1]',N'nvarchar(max)') AS DeviceNo
      ,@XML.value(N'(//License_x0020_Plate)[1]',N'nvarchar(max)') AS LicensePlate
      ,@XML.value(N'(//Driver)[1]',N'nvarchar(max)') AS Driver
      ,@XML.value(N'(//Date_x002F_Time)[1]',N'datetime') AS [DateTime];

注意：DateTime 显示为当地时间（不确定，测试一下）

更新

DECLARE @XML AS XML, @hDoc AS INT, @SQL NVARCHAR (MAX)

SELECT @XML = '<DataSet xmlns="http://www.example.com/">
  <diffgr:diffgram xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1">
    <NewDataSet xmlns="">
      <General_x0020_Report diffgr:id="General Report1" msdata:rowOrder="0">
        <Device_x0020_No>224610</Device_x0020_No>
        <License_x0020_Plate>AAA 123</License_x0020_Plate>
        <Driver>Driver Name</Driver>
        <Date_x002F_Time>2018-01-01T12:46:04+03:00</Date_x002F_Time>
      </General_x0020_Report>
      <General_x0020_Report diffgr:id="General Report1" msdata:rowOrder="0">
        <Device_x0020_No>2222</Device_x0020_No>
        <License_x0020_Plate>Some other</License_x0020_Plate>
        <Driver>One more</Driver>
        <Date_x002F_Time>2018-01-01T12:46:04+03:00</Date_x002F_Time>
      </General_x0020_Report>
     </NewDataSet>
  </diffgr:diffgram>
</DataSet>';
--The easy approach is the deep search with //, jumping right into the nodes of interest:

SELECT r.value(N'(Device_x0020_No)[1]',N'nvarchar(max)') AS DeviceNo
      ,r.value(N'(License_x0020_Plate)[1]',N'nvarchar(max)') AS LicensePlate
      ,r.value(N'(Driver)[1]',N'nvarchar(max)') AS Driver
      ,r.value(N'(Date_x002F_Time)[1]',N'datetime') AS [DateTime]
FROM @XML.nodes(N'//General_x0020_Report') AS A(r);