[Koha] problem with searching records

[Irakli Garibashvili]

Hi!

We have Koha 3.0, with Marc21 and Nozebra.

Unfortunately in many cases our searches (both from intranet or OPAC ) give 
either no results or errors (Error 404).

I have tried to trace the reason examining MYSql tables and found two 
problems, which to my mind, can lead to this situation:

1. Several records in Nozebra table have empty "biblionumbers" fields.
It looks like these indexes are not created....
Not sure - shall I run rebuild_nozebra.pl in cron?? Nightly?? Any 
documentation for this?

2. Several records in "biblioitems" table have empty "Marcxml" field.
Can I delete them manually or this will make other problems?
Is this filed used in searching somehow??

Can anybody help me?

Thanks in advance!

Irakli

Irakli Garibashvili (Mr.)
Georgian Library Association
#7 Gudiashvili Str. Tbilisi, 0107,
GEORGIA