Running pragma optimize on all connections

[YairHalberstadt]

https://www.sqlite.org/lang_analyze.html recommends running

PRAGMA analysis_limit=400;
PRAGMA optimize;

on each DB Connection just before it closes.

However as #255 points out, there is no way to do access all connections at the moment.

It's important that this be run on every connection, since each connection stores data about which tables need to be analyzed base on queries it ran.

I wonder if we could expose some API to do this?

Thanks!

[rittneje]

Perhaps we could add a CloseHook, analogous to the existing ConnectHook. That would be very flexible and would allow you to perform any such pre-close actions, log, etc. whenever an individual connection in the pool is closed.