Many thanks, Barton. I think that may have done it! I added an ISBN check (i.isbn not null or empty string) as otherwise the report was pulling many false duplicates.
Will have some happy catalogers now :-) All best, Cab Vinton Plaistow Public Library On Thu, Aug 16, 2018 at 9:48 AM, Barton Chittenden <bar...@bywatersolutions.com> wrote: > > > On Tue, Aug 14, 2018, 11:29 AM Cab Vinton <bibli...@gmail.com> wrote: >> >> Hi, All -- >> >> We're using the following report to identify records w/ duplicate ISBNs. >> >> SELECT GROUP_CONCAT(b.biblionumber SEPARATOR ', ') AS biblionumbers, >> b.title, b.author, GROUP_CONCAT(i.isbn SEPARATOR ', ') AS isbns >> FROM biblio b >> LEFT JOIN biblioitems i ON (i.biblionumber=b.biblionumber) >> GROUP BY CONCAT(substr(b.title,0,9),"/",i.isbn) >> HAVING COUNT(CONCAT(substr(b.title,0,9),"/",i.isbn))>1 > > > I think you should be able to use > > having count(*) > 1 >> >> >> We're a coop, however, so it would be helpful to limit the results to >> cases where our particular library owns at least one of the associated >> items. >> >> Adding the following lines did not provide correct results, unfortunately: >> >> LEFT JOIN items m ON (m.biblionumber=b.biblionumber) >> WHERE m.homebranch = <<Library|branches>> > > > I think the join is conflicting with your group by. Try using an exists() > statement in your where clause: > > WHERE EXISTS( > select * from items where b.biblionumber = items.biblionumber and > items.homebranch = <<Library|branches>> > ) > > This should be faster than a subquery because it will stop when it hits the > first item that makes the query in the exists statement true. _______________________________________________ Koha mailing list http://koha-community.org Koha@lists.katipo.co.nz https://lists.katipo.co.nz/mailman/listinfo/koha
