Unable to cast TEXT to XML in SQL Server

Question

Basically I have a column named XML that is of type TEXT; this cannot be changed for other reason, but I was wondering how I could cast it to XML.<

Answer 1

Your problem is: you have XML with an encoding="utf-16", but your column is a non-Unicode column......

Assuming that you cannot change it to NTEXT either, you have to do two nested CAST to achieve what you're looking for:

SELECT 
    CAST(CAST(XML AS NTEXT) AS XML).value('(/Record/UserGuid)[1]', 'NVARCHAR(max)')
FROM 
    tbl_Module_RequestForms_Items

First, you need to cast to NTEXT (or NVARCHAR(MAX)), and then you have to cast that result to XML, before you can use it.

Tip: remove those "other reasons" and convert this to XML datatype if you really need to use it as XML .....

Answer 2

You should replace encoding="utf-16" to encoding="utf-8" or ''(blank) and then perform your operation.

a. Converting encoding="utf-16" to encoding="utf-8"

SELECT 
  CAST(
    REPLACE(CAST([xml] AS VARCHAR(MAX)), 'encoding="utf-16"', 'encoding="utf-8"')
  AS XML).value('(/Record//UserGuid/node())[1]', 'NVARCHAR(max)') as UserGuid
from tbl_Module_RequestForms_Items

b. Replacing encoding="utf-16" to ''(blank)

SELECT 
  CAST(
    REPLACE(CAST([xml] AS VARCHAR(MAX)), 'encoding="utf-16"', '')
  AS XML).value('(/Record//UserGuid/node())[1]', 'NVARCHAR(max)') as UserGuid
from tbl_Module_RequestForms_Items

Answer 3

Replacing encoding="utf-8" to encoding="utf-16" worked for me :)

Answer 4

You need to change the encoding before casting to XML.

CAST (REPLACE(MyTextToCastToXML, 'utf-8', 'utf-16') AS XML)

Answer 5

Have you tried CONVERT instead of CAST?

SELECT CONVERT(XML, @xml).value('(/Record/UserGuid)[1]', 'NVARCHAR(max)')
from tbl_Module_RequestForms_Items

Also, check out the "xml styles" section of this page; it contains some options you have when converting xml:

http://msdn.microsoft.com/en-us/library/ms187928.aspx

Answer 6

Casting XML variable as NTEXT solves the problem CAST(CAST (XML AS NTEXT) AS XML).