On Mon, Mar 07, 2005 at 07:18:05PM -0500, Stephen Hedges said:
Chris' solution still won't give you an accurate issue date, since he
presumes that people renew items on the date_due -- and we all know that
borrowers are not that dependable (damn!). Adding the issue_date to the
issues table seems to be the only way to get an accurate statistic.
Yep it makes that assumption it also makes the assumption that none of the
due_dates have been overriden (which you can do in circulation).
I think it may be the only way to get an approximation of the average loan
length with the data as it stands.
Going forward we should add an issue_date column to the table, if that is
useful data to know.
I'm curious, Henri-Damien -- are you trying to do a daily statistics
report? Is that why you need the issue date?
I think he is trying to work out average loan length, which would be an
interesting statistic to know.
Daily stats you can figure out from the statistics table.
Chris