Reading XML that is saved as text from SQL

Question

This is what my query looks like:

select top 5   cast(content_html as xml) as [prodxml],
prodxml.value('data(ClassTemplate[1]', 'nvarchar(max) ') as prod2
from content 
where 
end_date >= getdate()
and folder_id != 71682 

and I keep getting:

Msg 4121, Level 16, State 1, Line 1
Cannot find either column "prodxml" or the user-defined function or aggregate "prodxml.value", or the name is ambiguous.

what am I doing wrong?

Answer 1

I cannot directly request prod1, how else can I find all entries that have "Other" as a class template?

You cannot reference a column alias in another column of the same SELECT statement - use:

SELECT TOP 5   
       CAST(t.content_html AS XML).value('(/root/ClassTemplate)[1]', 'NVARCHAR(max)') AS prod2
  FROM CONTENT t
 WHERE t.end_date >= getdate()
   AND t.folder_id != 71682 

If you want to filter based on the value of prod2 in the WHERE clause, use:

  FROM CONTENT t
 WHERE CAST(t.content_html AS XML).value('(/root/ClassTemplate)[1]', 'NVARCHAR(max)') = 'Other'
   AND t.end_date >= getdate()
   AND t.folder_id != 71682