For a test you might want to try also this approach (both from perl and from psql):
$dbh->do('PREPARE sth_tim (int,inet,boolean,timestamptz) AS INSERT INTO timestamps VALUES ($1,$2,$3,$4)'); $sth_tim = $dbh->prepare("EXECUTE sth_tim(?,?,?,?)");
...and later execute it. (and likewise with psql). If you'll see gain in speed with perl it means your DBD::Pg wasn't using server side prepared statements.
The intent of prepared statements is to reduce the overhead of running the parser, rewriter and planner multiple times for a statement that is executed multiple times. For an INSERT query without any sub-selects that is not rewritten by any rules, the cost to parse, rewrite and plan the statement is trivial. So I wouldn't expect prepared statements to be a big win -- you would gain a lot more from batching multiple inserts into a single transaction, and more still from using COPY.
-Neil
---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
