[Koha] Report help needed

[Elaine Bradtke]

I'm trying to find records lacking 300 fields. The following keeps
failing.  Any help would be appreciated. Thanks!

SELECT CONCAT('<a href=\"/cgi-bin/koha/catalogue/detail.pl?biblionumber=
',biblionumber,'\">',biblionumber,'</a>')
AS bibnumber
FROM
(SELECT biblionumber,
ExtractValue(metadata,'//datafield[@tag="300"]/subfield[@code>="a"]') AS
suba,
ExtractValue(metadata,'//datafield[@tag="300"]/subfield[@code>="b"]') AS
subb,
ExtractValue(metadata,'//datafield[@tag="300"]/subfield[@code>="3"]') AS
sub3,
FROM biblio_metadata) AS subfields
WHERE suba = ""
AND subb = ""
AND sub3 = ""

Elaine Bradtke
VWML <https://www.vwml.org>
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