I'm performing a very simple query (no joins) using a stored procedure on a
table with about a million of records. The query retrieves a single record.
On the table there is an index that is used by the query (i've checked the
plan) to perform the search.
I'm experiencing a very slow response time (8/10 minutes) of this query the
first time it's executed after a long period of idleness of the server
(i.e., during the night the software it's not used and the delay is
experieced in the morning). After the first query all the system becomes
responsive as it usually has been in the past (there were less record in
the past, but they grow constantly while the delay has beed reported to
appear suddendly).
The server is Firebird 1.0.3
I've performed usual maintenance doing a backup and restore and i've
recomputed all indexes (this is also done during restore i think).
Anyone has some ideas on what can i do to solve this problem?

ciao