SQL: How can I get the value of an attribute in XML datatype?

Question

I have the following xml in my database:

<email>
  <account language="en" ... />
</email>

I am using something like this now: but still have to find the attribute value.

 SELECT convert(xml,m.Body).query('/Email/Account')
 FROM Mail

How can I get the value of the language attribute in my select statement with SQL?

Fantasm

Answer 1

Use XQuery:

declare @xml xml =
'<email>
  <account language="en" />
</email>'

select @xml.value('(/email/account/@language)[1]', 'nvarchar(max)')

---

declare @t table (m xml)

insert @t values 
    ('<email><account language="en" /></email>'), 
    ('<email><account language="fr" /></email>')

select m.value('(/email/account/@language)[1]', 'nvarchar(max)')
from @t

Output:

en
fr

Adipose

this worked perfect! select @xml.value('(/email/account/@language)[1]', 'nvarchar(max)') THANK YOU! – Fantasm

@KirillPolishchuk What if a root element contains an xmlns attribute? Say, <email xmlns="http://domain.com/ws/2016-08-07>. In this case XQuery returns NULL. – Malenamalet

@InterfaceUnknown, this is called "Default namespace". Something like this: set namespace before select command like this: WITH XMLNAMESPACES ('http://domain.com/ws/2016-08-07' as x ). Then you can add reference to this namespace in the select query: '(/x:email/x:account/@language)[1]' – Adipose

Answer 2

This should work:

DECLARE @xml XML

SET @xml = N'<email><account language="en" /></email>'

SELECT T.C.value('@language', 'nvarchar(100)')
FROM @xml.nodes('email/account') T(C)

Wadi

Answer 3

It depends a lot on how you're querying the document. You can do this, though:

CREATE TABLE #example (
   document NText
);
INSERT INTO #example (document)
SELECT N'<email><account language="en" /></email>';

WITH XmlExample AS (
  SELECT CONVERT(XML, document) doc
  FROM #example
)
SELECT
  C.value('@language', 'VarChar(2)') lang
FROM XmlExample CROSS APPLY
     XmlExample.doc.nodes('//account') X(C);

DROP TABLE #example;

EDIT after changes to your question.

Adze

I've edited my question. the xml is saved as ntext in the database. I convert it first to xml type. – Fantasm

See my edits, using ntext input and a table approach with CTE to transform to xml. – Adze

Answer 4

if the xml data is stored in sql server as a string column then use cast

select cast(your_field as XML)
       .value('(/email/account/@language)[1]', 'varchar(20)') 
from your_table

Buckbuckaroo