[Koha] Report help needed - modification date

[Elaine Bradtke]

How do I filter records based on the MARC 005?  DATE AND TIME OF LATEST
TRANSACTION
biblio.timestamp doesn't do it.

This is what I have:
SELECT
 biblio.biblionumber,items.barcode,biblio.author,biblio.title,biblio.timestamp,biblio.datecreated
FROM items LEFT JOIN biblioitems on
(items.biblioitemnumber=biblioitems.biblioitemnumber) LEFT JOIN biblio on
(biblioitems.biblionumber=biblio.biblionumber)   WHERE biblio.timestamp >=
'2014-05-01' AND biblio.timestamp <= '2014-05-30' ORDER BY
biblio.biblionumber asc

In the guided report the option I chose was Modification date /
biblio.timestamp

But after testing this I've discovered that  it isn't using the date in the
005.  I'm not sure where the  Modification date / biblio.timestamp
information is coming from, it's neither the creation date, nor the
modification date, but some other date entirely.

I'm trying to hunt down a batch of records modified on a certain date.
Thanks for any help.

-- 
Elaine Bradtke
Data Wrangler
VWML
English Folk Dance and Song Society | http://www.efdss.org
Cecil Sharp House, 2 Regent's Park Road, London NW1 7AY
Tel    +44 (0) 20 7485 2206 (This number is for the English Folk Dance and
Song Society in London, England. If you wish to phone me personally, send
an e-mail first. I work off site)
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"Writing about music is like dancing about architecture"
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