What is the function of the "itemnumber" field in the
"items" table in Koha? Where does it come from? How
is it used?
In the MARC/Koha cross reference document on
http://www.koha.org/wiki
(which I realize is woefully out of date) the "itemnumber" field references MARC tag 890, subfield "c", which, as far as I can tell is not used elsewhere in Koha. In fact, neither MARC21 nor UNIMARC define tag 890 at all (see http://www.loc.gov/marc/bibliographic/ and http://www.ifla.org/VI/3/p1996-1/sec-uni.htm for tag definitions under MARC21 and UNIMARC, respectively).
I have tried to put together a cross reference spreadsheet based not only on the cross reference document noted above, but also by reference to fields defined in Koha.
Any information I can get on this or related questions will be appreciated.
Thanks,
Tom Madron