如何在 MS SQL 2005 中使用 SQL XQuery 修改多个节点 [英] How to modify multiple nodes using SQL XQuery in MS SQL 2005

问题描述

在一张表中，我有以下内容.

In an table I have the following.

ParameterID (int)    ParameterValue (XML)
------------    --------------
1               <USER><User ID="1" Name="Billy"/><USER>
                <USER><User ID="2" Name="Billy"/><USER>
                <MANAGER><User ID="1" Name="Billy"/><MANAGER>
2               <USER><User ID="1" Name="John"/><USER>
                <USER><User ID="2" Name="Billy"/><USER>
                <MANAGER><User ID="1" Name="Billy"/><MANAGER>
3               <USER><User ID="1" Name="David"/><USER>
                <USER><User ID="2" Name="Billy"/><USER>
                <MANAGER><User ID="1" Name="Billy"/><MANAGER>

如何将 Billy 的所有实例修改为 Peter?

How do I modify all instances of Billy to be Peter?

我试过了

-- Update the table         
UPDATE  @tbXML
SET     ParameterValue.modify('replace value of (//User/@Name[.="Billy"])[1] with "Peter"')

但只有行中的第一个 Billy 被更新.

But only the first Billy in the row was updated.

多次运行更新:

For Row 1: 
1st Time = 1 <USER><User ID="1" Name="Peter"/><USER> <USER><User ID="2" Name="Billy"/><USER> <MANAGER><User ID="1" Name="Billy"/><MANAGER> 

2nd Time 1 <USER><User ID="1" Name="Peter"/><USER> <USER><User ID="2" Name="Peter"/><USER> <MANAGER><User ID="1" Name="Billy"/><MANAGER> 

3rd Time 1 <USER><User ID="1" Name="Peter"/><USER> <USER><User ID="2" Name="Peter"/><USER> <MANAGER><User ID="1" Name="Peter"/><MANAGER>

推荐答案

简单"的方法是将 XML 列转换为 VARCHAR(MAX) 并简单地对其进行 REPLACE:

The "simple" approach would be to cast the XML column to VARCHAR(MAX) and just simply do a REPLACE on it:

UPDATE
  YourTable
SET
  ParameterValue = CAST(REPLACE(CAST(ParameterValue AS VARCHAR(MAX)), '
                                Billy', 'Peter') AS XML)
WHERE
  ....

就像 Richard Szalay 解释的那样，您几乎无法在单个 UPDATE 语句中更新多个 XML 节点值这里:

It almost seems like you cannot do an update of multiple XML node values in a single UPDATE statement, as Richard Szalay explains here:

不幸的是，该实现似乎受到了极大的限制，因为它无法在一次更新中对同一值进行任意数量的修改.

所以我猜你要么必须使用上面提到的愚蠢"的 VARCHAR(MAX) 方法，要么在循环中进行更新(当你仍然找到一个带有billy"的节点时，更新该节点以读取彼得"代替).

So I guess you'll either have to use the "dumb" VARCHAR(MAX) approach mentioned above, or do the update in a loop (WHILE you still find a node with "billy", UPDATE that node to read "Peter" instead).

马克

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