Comment 5 for bug 1744341

Michele, one reason we retain the copy maps for frozen holds is the maps are used to calculate hold queue position. When the maps don't exist, the holds are ignored when calculating queue positions for holds in the same queue.

Arguably it's a bug that holds suspended at placement time have no copy maps.

Related to this, I'm considering opening a new LP to change (or offer an alternative to) how we calculate the queue position. The hold copy map table is large with a lot of turn-over, so querying the table is not always fast.

As of EG 2.12, "reporter.hold_request_record" is a proper database table that's quick to query. This table can be used to calculate queue positions if you define the hold queue position as all holds (across all types) that ultimately target the same bib record. It changes the meaning a bit, but the exact values don't mean as much as how they change over time. We've been using it locally to great effect.