SQL Server XML-DML如何将元素值替换为相对xpath的值

Question

我有一个包含以下数据的xml列：

<Policy>
  <Name>
    <Id>adf</Id>
    <First>Alan</First>
    <Last>Turing</Last>
  </Name>
  <Name>
    <Id>asdf</Id>
    <Business>Vandelay Industries</Business>
  </Name>
  <Name>
    <Id>asdf</Id>
    <First>Dennis</First>
    <Last>Ritchie</Last>
  </Name>
</Policy>

如何编写XML-DML查询来替换所有行中每个名称的Id元素的值，使其包含First、Last和Business的值。例如：

<Policy>
  <Name>
    <Id>AlanTuring</Id>
    <First>Alan</First>
    <Last>Turing</Last>
  </Name>
  <Name>
    <Id>Vandelay Industries</Id>
    <Business>Vandelay Industries</Business>
  </Name>
  <Name>
    <Id>DennisRitchie</Id>
    <First>Dennis</First>
    <Last>Ritchie</Last>
  </Name>
</Policy>

以下是我失败的尝试：

update policy set data.modify('
  replace value of (//Name/Id/text())[1] 
  with concat(
    (//Name/First/text())[1], 
    (//Name/Last/text())[1], 
    (//Name/Business/text())[1])') 

这会产生以下结果：

<Policy>
  <Name>
    <Id>AlanTuringVandelay Industries</Id>
    <First>Alan</First>
    <Last>Turing</Last>
  </Name>
  <Name>
    <Id>asdf</Id>
    <Business>Vandelay Industries</Business>
  </Name>
  <Name>
    <Id>asdf</Id>
    <First>Dennis</First>
    <Last>Ritchie</Last>
  </Name>
</Policy>

Answer 1

这是可行的。

declare @i int
declare @maxNames int
set @i = 1
set @maxNames = (select max(data.value('count(//Name)', 'int')) from Policy)
while @i <= @maxNames begin
    update policy set data.modify('
      replace value of (//Name[sql:variable("@i")]/Id/text())[1] 
      with concat(
        (//Name[sql:variable("@i")]/First/text())[1], 
        (//Name[sql:variable("@i")]/Last/text())[1], 
        (//Name[sql:variable("@i")]/Business/text())[1])
    ') 
    set @i = @i + 1
end

Answer 2

基于集合的选项如下所示：

    update policy 
    set data.modify('
    replace value of (//Name[sql:column("id")]/Id/text())[1]
    with concat(
    (//Name[sql:column("id")]/First/text())[1],
    (//Name[sql:column("id")]/Last/text())[1],
    (//Name[sql:column("id")]/Business/text())[1])
    ')