Emi Lu <emilu@encs.concordia.ca> writes:
> In another way, whenever we "delete/truncate and then insert" data into
> a table, it is better to "vacuum anaylze"?
You shouldn't need a VACUUM if you haven't yet done any updates or
deletes since the TRUNCATE. An ANALYZE seems like a good idea, though.
(You could get away without ANALYZE if the new data has essentially the
same statistics as the old, but if you're making only minor changes, why
are you using this technique at all ...)
regards, tom lane