SQL XML选择值

Question

How can I select the 'value' within this return.

<int xmlns="http://schemas.microsoft.com/2003/10/Serialization/">247734</int>

I have tried

DECLARE @XML XML
SET @XML = '<int xmlns="http://schemas.microsoft.com/2003/10/Serialization/">247734</int>'

SELECT  @XML.value('(/int)[1]', 'varchar(30)')
FROM    @xml.nodes('/int') Tbl ( Col )

But I return no value.

Answer 1

You can define an alias for the namespace and then use that alias in the xpath.

Without specifying a namespace, an xpath would only find tags without a namespace.

Or you could look in the xpath for any namespace *:

For example:

DECLARE @XML XML = N'<xml>
  <int xmlns="http://schemas.microsoft.com/2003/10/Serialization/">247734</int>
  <int>123</int>
</xml>';

-- method 1
;WITH XMLNAMESPACES('http://schemas.microsoft.com/2003/10/Serialization/' AS s)
SELECT  Col.value('.', 'int') as Col
FROM    @XML.nodes('//s:int') Tbl (Col);

-- method 2
SELECT  Col.value('.', 'int') as Col
FROM    @XML.nodes('//*:int') Tbl (Col);

Notice how method 1 only finds the first value, while method 2 finds both.

Answer 2

Try Following

DECLARE @XML XML
SET @XML = '<int xmlns="http://schemas.microsoft.com/2003/10/Serialization/">247734</int>'

SELECT Col.value('(.)[1]', 'int')
FROM @xml.nodes('//*') As Tbl (Col )

Answer 3

This issue is your XML is in a defined namespace, and you are trying to select using the "default namespace".

To fix the issue you should define the namespace in your selection:

DECLARE @XML XML
SET @XML = '<int xmlns="http://schemas.microsoft.com/2003/10/Serialization/">247734</int>'

SELECT @XML.value('declare namespace ns="http://schemas.microsoft.com/2003/10/Serialization/"; (/ns:int)[1]', 'varchar(30)' )  
FROM   @xml.nodes('/') Tbl ( Col )