• Article Type: General
• Product: Aleph 
• Product Version: 20, 21, 22, 23

Description:
What updates cause a z30h item history record to be written? It seems that more are being written than need to be.

Resolution:
KCS article No History records for certain items **MASTER RECORD** discusses the conditions for z30h record creation.

The reason for the writing of the z30h is recorded in the z30h_h_reason. Possible values, from ./xxx50/tab/tab_item_history.eng, are:

ITEM-LOCATION       L Location
ITEM-CALL-NO-2      L Location2
ITEM-COLLECTION     L Collection
ITEM-SUB-LIBRARY    L Sublibrary
ITEM-PROCESS-STATUS L Process Status
ITEM-BARCODE        L Barcode
BIND                L Deleted (Bound)
DELETE              L Deleted
ITEM-STATUS         L Status
SHELF-REPORT-NUMBER L Inventory Check
ITEM-MATERIAL       L Material Type
ITEM-DESCRIPTION    L Item Desc.
ITEM-CIRC-NOTE      L Circ Note
ITEM-INT-NOTE       L Internal Note
ITEM-OPAC-NOTE      L OPAC note
ITEM-LOCATION-TYPE  L Location Type
ITEM-CALL-NO-2-TYPE L Location2 Type
ITEM-COPY           L Copy Number
ITEM-ENUM-A         L Enum Level 1
ITEM-ENUM-B         L Enum Level 2
ALL-FIELDS          L All fields

If "ALL-FIELDS" is specified, then a z30h record will be written for each loan (update of z30h_no_loans) and return (update of z30h_last_return_date). We strongly suggest the use of "ALL-NON-CIRC" instead of "ALL-FIELDS". From the tab_item_history header:

! Use "ALL-NON-CIRC" in order to register all changes except
! of item changes caused as a result of item's circulation activities
! (Z30_DATE_LAST_RETURN, Z30_HOUR_LAST_RETURN, Z30_IP_LAST_RETURN,
! Z30_NO_LOANS and Z30_MAINTENANCE_COUNT).
 

You could  delete all of the z30h records which have only "All fields" as the reason for their being written and which are older than a year.   This SQL would be used for that:

SQL> delete from z30h where Z30H_H_REASON = 'All fields' and z30h_h_date < 'yyyymmdd';

Note that this will *not* delete z30h records which have a Z30H_H_REASON field with other reasons in addition to 'All fields'.

But note that "ALL-FIELDS" includes all of the "ALL-NON-CIRC" fields in addition to the above.  So when "ALL-NON-CIRC" has not been specified, then the deletion of "ALL-FIELDS" records will delete records which were updated for those other reasons as well.

You should back up the z30h with the file-03 Service before running this.

See also the article,  " Best practices - retention of item/circ history tables " in regard to deleting old z30h records.

• Article last edited: 9-Feb-2016