non-title holds can be hidden from View Holds tab when bib changes

A little more data, the specific issue that the on UPDATE the trigger function skips re-assigning the record value if the target and hold_type have remained the same ... which of course does not mean that the parent bib hasn't changed. We could fix that my basically flattening out the trigger function to always run but that's a lot of overhead for every hold update versus a relatively uncommon merging of records. I'm more inclined to add logic to merging record assets to address this but that has the disadvantage of essentially duplicating logic in two places which is .... not good.

For seeing affected holds:

select ahr.id, 'V' as hold_type
from reporter.hold_request_record rhrr
join action.hold_request ahr on ahr.id = rhrr.id
join asset.call_number acn on acn.id = ahr.target
where ahr.fulfillment_time is null and ahr.cancel_time is null and (ahr.expire_time is null or ahr.expire_time > now()) and ahr.hold_type = 'V'
and acn.record != rhrr.bib_record
UNION ALL
select ahr.id, 'C' as hold_type
from reporter.hold_request_record rhrr
join action.hold_request ahr on ahr.id = rhrr.id
join asset.copy ac on ac.id = ahr.target
join asset.call_number acn on acn.id = ac.call_number
where ahr.fulfillment_time is null and ahr.cancel_time is null and (ahr.expire_time is null or ahr.expire_time > now()) and ahr.hold_type = 'C'
and acn.record != rhrr.bib_record
UNION ALL
select ahr.id, 'P' as hold_type
from reporter.hold_request_record rhrr
join action.hold_request ahr on ahr.id = rhrr.id
join biblio.monograph_part bmp on bmp.id = ahr.target
where ahr.fulfillment_time is null and ahr.cancel_time is null and (ahr.expire_time is null or ahr.expire_time > now()) and ahr.hold_type = 'P'
and bmp.record != rhrr.bib_record
;

This is still occurring in 3.8.0.

 Merging records does not fully transfer non-title holds to the target record. The hold remains and will process correctly but is not visible in the current record view holds. It is visible in the patron record and on the merged and deleted record

Transferring volumes/items may also have the same issue.

This is still an issue in 3.9.2.

A record with part-level holds was merged (as lead) with another record. The holds are no longer visible under View Holds, but are accessible via the patron accounts.