[Koha] Koha Database Maintenance

[ISM KIS]

Test upgrade to 3.4 showed that our database must have some corrupt records.

Upgrading our current database fails on 
 misc/maintenance/remove_items_from_biblioitems.pl --run 
and on
 misc/migration_tools/rebuild_zebra.pl -b -r

However if I restore and upgrade an earlier version the upgrade is ok.

Is there a way to verify and clean-up a koha database?
Any script to check the consistency?

Rudy Wuthrich
Kodaikanal International School