将每个子标记转换为具有多个分隔符的单列 (SQL Server)

Question

这是我的 XML

<plan>
  <prescription>
    <name>ABC</name>
    <frequency>Daily</frequency>
    <dailyfrequency>
       <morning>2</morning>
       <afternoon></afternoon>
       <night>1</night>
    </dailyfrequency>
  </prescription>
  <prescription>
    <name>EDF</name>
    <frequency>Daily</frequency>
    <dailyfrequency>
      <morning>5</morning>
      <afternoon>5</afternoon>
      <evening>4</evening>
      <night>1</night>
   </dailyfrequency>
   <dayfrequency></dayfrequency>
  </prescription>
  <prescription>
    <name>YTER</name>
    <frequency>Weekly</frequency>
    <dailyfrequency>
      <morning>5</morning>
      <afternoon>5</afternoon>
      <evening>4</evening>
      <night>1</night>
    </dailyfrequency>
    <dayfrequency>Monday,Tuesday,Wednesday</dayfrequency>
  </prescription>
</plan>

我使用交叉连接进行如下查询

PLAN=    STUFF(XMLData.query('for $a in 
    (*:ClinicalDocuments/Visits/Visit/prescriptions/prescription) 

return <a>{concat("$", $a)}</a>').value('.', 'NVARCHAR(MAX)'), 1, 1, '') 

但是我的结果会这样显示

**PLAN**
ABCDaily21$EDFDaily5541$YTERWeekly5541Monday,Tuesday,Wednesday

但我真的很想像下面这样（假设$-处方内每个标签的分隔符，！-列分隔符每个处方本身）

**PLAN**
ABC$Daily$2$0$0$1$0!EDF$Daily$5$5$4$1$0!YTER$Weekly$5$5$4$1$Monday,Tuesday,Wednesday

请任何人在这里帮助我！

（注意：某些子标签可能不存在，即表示它没有值）

非常感谢，Jayendran

Answer 1

以下可能是您需要的，但我真的不知道您想如何处理 不存在的元素。在您的示例中，您放置了0，但这不是缺失值，而是专用默认值。这需要一些关于底层数据类型的知识......

试试这个：

DECLARE @xml XML=
N'<plan>
  <prescription>
    <name>ABC</name>
    <frequency>Daily</frequency>
    <dailyfrequency>
       <morning>2</morning>
       <afternoon></afternoon>
       <night>1</night>
    </dailyfrequency>
  </prescription>
  <prescription>
    <name>EDF</name>
    <frequency>Daily</frequency>
    <dailyfrequency>
      <morning>5</morning>
      <afternoon>5</afternoon>
      <evening>4</evening>
      <night>1</night>
   </dailyfrequency>
   <dayfrequency></dayfrequency>
  </prescription>
  <prescription>
    <name>YTER</name>
    <frequency>Weekly</frequency>
    <dailyfrequency>
      <morning>5</morning>
      <afternoon>5</afternoon>
      <evening>4</evening>
      <night>1</night>
    </dailyfrequency>
    <dayfrequency>Monday,Tuesday,Wednesday</dayfrequency>
  </prescription>
</plan>';

更新：添加了一个谓词以排除 <dailyfrequence>

SELECT STUFF(
(
    SELECT '!' + STUFF(p.query(N'for $n in .//*[local-name()!="dailyfrequency"]
                           return <a>{concat("$",($n/text())[1])}</a>'
                        ).value(N'.',N'nvarchar(max)'),1,1,'')
    FROM @xml.nodes(N'/plan/prescription') AS A(p)
    FOR XML PATH(''),TYPE).value(N'.',N'nvarchar(max)'),1,1,'')

结果

ABC$Daily$2$$1!EDF$Daily$5$5$4$1$!YTER$Weekly$5$5$4$1$Monday,Tuesday,Wednesday

缺失值用无值表示。