I like cross-session query plan caching talk. I would prefer if the
function was optional (i.e. per-session "use cross-session query plan
cache" variable).
I like the "automatic re-plan if the estimate did not match the actual"
idea with some softening technique involved such as "if the last 3 times
it ran, it did the wrong thing, learn from our mistake and adapt".
The other ideas about automatically deciding between plans based on
ranges and such strike me as involving enough complexity and logic, that
to do properly, it might as well be completely re-planned from the
beginning to get the most benefit.
Cheers,
mark
--
Mark Mielke <mark@mielke.cc>