带有 SQL 的 XML 节点

如何解决带有 SQL 的 XML 节点

我有以下 XML 数据，并希望按如下方式在 KS 中获取数据：

<DW>
  <KS>
    <KeyInfo Name="IlluSetting">
      <KeyTypeValue>Text</KeyTypeValue>
      <ValueString>yDipol90</ValueString>
    </KeyInfo>
     <KeyInfo Name="IlluSetting2">
      <KeyTypeValue>Text</KeyTypeValue>
      <ValueString>yDipol</ValueString>
    </KeyInfo>
  </KS>
  <MDESC>Tx [mrad]</MDESC>
   <MNUMBER>0.12102</MNUMBER>
</DW>
<DW>
  <KS>
    <KeyInfo Name="IlluSetting3">
      <KeyTypeValue>Text</KeyTypeValue>
      <ValueString>yDipol80</ValueString>
    </KeyInfo>
  </KS>
  <MDESC>Ty [mrad]</MDESC>
  <MNUMBER>0.12102</MNUMBER>
</DW>

有什么办法可以得到一个具有以下输出的表格：

Name            ValueString     Name            ValueString
-----------------------------------------------------------
IlluSetting     yDipol90        IlluSetting2    yDipol
IlluSetting3    yDipol80    

表示<KS>... </KS>里面的数据会排成一行显示

非常感谢

解决方法

请尝试以下解决方案。我们在这里所做的称为粉碎，即将 XML 转换为矩形/关系格式。

我正在拍摄，因为没有提供DDL 和样本数据群。

由于缺少根元素，提供的 XML 格式不正确，但 SQL Server 允许处理 XML 片段。

我们正在使用 XQuery 及其 .nodes() 和 .value() 方法。

SQL，方法 #1

-- DDL and sample data population,start
DECLARE @xml XML =
N'<DW>
    <KS>
        <KeyInfo Name="IlluSetting">
            <KeyTypeValue>Text</KeyTypeValue>
            <ValueString>yDipol90</ValueString>
        </KeyInfo>
        <KeyInfo Name="IlluSetting2">
            <KeyTypeValue>Text</KeyTypeValue>
            <ValueString>yDipol</ValueString>
        </KeyInfo>
    </KS>
    <MDESC>Tx [mrad]</MDESC>
    <MNUMBER>0.12102</MNUMBER>
</DW>
<DW>
    <KS>
        <KeyInfo Name="IlluSetting3">
            <KeyTypeValue>Text</KeyTypeValue>
            <ValueString>yDipol80</ValueString>
        </KeyInfo>
    </KS>
    <MDESC>Ty [mrad]</MDESC>
    <MNUMBER>0.12102</MNUMBER>
</DW>';
-- DDL and sample data population,end

SELECT c.value('KeyInfo[1]/@Name','VARCHAR(30)') AS name1,c.value('(KeyInfo[1]/ValueString/text())[1]','VARCHAR(30)') AS ValueString1,COALESCE(c.value('KeyInfo[2]/@Name','VARCHAR(30)'),'') AS name2,COALESCE(c.value('(KeyInfo[2]/ValueString/text())[1]','') AS ValueString2
FROM @xml.nodes('/DW/KS') AS t(c);

输出

+--------------+--------------+--------------+--------------+
|    name1     | ValueString1 |    name2     | ValueString2 |
+--------------+--------------+--------------+--------------+
| IlluSetting  | yDipol90     | IlluSetting2 | yDipol       |
| IlluSetting3 | yDipol80     |              |              |
+--------------+--------------+--------------+--------------+

SQL，方法 #2

DECLARE @CrLf CHAR(2) = CHAR(13) + CHAR(10),@tokenCounter INT,@i INT = 1;

-- Calculate max number of tokens in the <KS>
SET @tokenCounter = (SELECT MAX(c.value('count(KeyInfo)','INT'))
FROM @xml.nodes('/DW/KS') AS t(c));

DECLARE @SQL NVARCHAR(MAX) = 'SELECT ';

WHILE @i <= @tokenCounter BEGIN
    SET @SQL += IIF(@i>1,','') + 'COALESCE(c.value(''KeyInfo[' + CAST(@i AS VARCHAR(3)) + ']/@Name'',''VARCHAR(30)''),'''') AS NAME' + CAST(@i AS VARCHAR(3)) + @CrLf
    SET @SQL += ',COALESCE(c.value(''(KeyInfo[' + CAST(@i AS VARCHAR(3)) + ']/ValueString/text())[1]'','''') AS ValueString' + CAST(@i AS VARCHAR(3)) + @CrLf

    SET @i += 1
END

SET @SQL += 'FROM @xml.nodes(''/DW/KS'') AS t(c);';

-- just to see it
PRINT @sql;

-- we are ready at this point
EXEC sp_executesql @stmt = @SQL,@params = N'@xml xml',@xml = @xml;