$sql = "INSERT INTO tabreserves(
  date_reserve, hour_i, hour_e, date,
  fk_idclient, fk_idfield, fk_iduser,name_temp,
  value, vat_perc, vat_val,desc_perc, desc_val,
  total, nhours)
VALUES(NOW(),?,?,?,?,?,?,?,?,?,?,?,?,?,?);
SELECT currval('public.tabreserves_idreserve_seq'::text)

$sth = $dbh->prepare($sql);
		
$sth->execute(
<values_goes_here>
);
$sth->bind_columns(\(my $new_id_reserve));
$sth->fetch();