Items unlinked from holdings record

Description

We have found a collection of item records (an example being 004545901-10)  that are not linked to their holdings. Is there a way to find out how these came unlinked?  

Resolution

As can be seen by comparing z30h_rec_key 004545901-000010-000002 (an item history record) to the current 004545901-10 z30 record, on March 11, 2016, at 15:49, its z30_hol_doc_number_x changed from 005974979 to the current 006763023. And, as can be seen from the last CAT field in the xxx60 006763023 HOL record: 

CAT L $$c20160311$$lXXX60$$h1817 

that record was deleted that same day at 18:17. (But note that it lacks any $$a subfield indicating the user or process that performed the deletion.)

In this case, it seems that this HOL record was accidentally deleted as part of cleaning up a bad manage-50 load.  It seems that when an HOL record is being deleted the system doesn't always warn you of the fact that there are still items linked to the HOL record. 

• Article last edited: 14-Apr-2016