[Koha] Unknown column 'metadata' in 'field list'

[Vimal Kumar V.]

Dear Friends,
I am trying to generate a book list with keywords from 650$a using the
following SQL query,

SELECT ExtractValue( metadata,
'//datafield[@tag="650"]/subfield[@code="a"]' ) AS Keyword, items.barcode,
items.dateaccessioned, items.itemcallnumber, biblio.author, biblio.title,
biblioitems.pages, biblioitems.publishercode, biblioitems.place,
biblio.copyrightdate
FROM items
LEFT JOIN biblioitems ON
(items.biblioitemnumber=biblioitems.biblioitemnumber)
LEFT JOIN biblio ON (biblioitems.biblionumber=biblio.biblionumber)
ORDER BY LPAD(items.barcode,40,' ') ASC

After running the report, I got the following error message,

The database returned the following error:
Unknown column 'metadata' in 'field list'
Please check the log for further details.

Please review the SQL query and help me to solve the problem.


Regards,
-- 
Vimal Kumar V.
Librarian
School of Indian Legal Thought
Mahatma Gandhi University
Kottayam, Kerala
Web: http://www.vimalkumar.info
Blogs: http://linuxhalwa.blogspot.com http://kohageek.blogspot.in
http://dspacegeek.blogspot.in
http://moovandan.blogspot.in  <http://moovandan.blogspot.in>
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