Unfortunatly the query need that level of complxity as the information I
have to show are spread around different table.
I have tryed the geqo on at the beginning but only with the default
parameters.
Tomorrow (my working day here in Italy is finished some minutes ago, so
I will wait for the end of the explain analyze and the go home ;-P )
I'll try to increase, as you suggest, join_collapse_limit and
from_collapse_limit.
If someone can give me some information on how to configure geqo, I'll
try it again.
In the meantime this night I leave the vacuum verbose to work for me.