Last Circulation or Creation Date reporting source could be made faster

[Galen Charlton]

We saw a weeding report that took three hours to run. Upon examining it, some things that jump out were:

* it uses the IDL view "rlc" (AKA "Last Circulation or Creation Date") to get at the last date that the item was created or circulationed
* "rlc" uses the DB view action.all_circulation to get for the last circ date from action.circulation & action.aged_circulation
* However, "rlc" doesn't need action.all_circulation per se, since it makes no reference to the user, item, or call number. it could use action.all_circulation_slim instead

Empirically, updating "rlc" to used action.all_circulation_slim resulted in a query plan that omits the sequential scan on action.aged_circulation found in the original query as well as joins and sequential scans on actor.usr, actor.usr_address, asset.copy, and action.call_number.

Consequently, updating the definition of "rlc" could provide a significant speed boost for reporter queries that include that reporting source.

[Galen Charlton (gmc)]

A patch is available in working/user/gmcharlt/lp2059813_speed_up_rlc / https://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/gmcharlt/lp2059813_speed_up_rlc