use Data::Dumper;
my $sth = $dbh->prepare($sql2);
$dbh->{RaiseError} = 1;
foreach my $i (0 .. @date1 - 1) {
    eval {
         $sth->execute($date1[$i], $date2[$i]);
         my @row;
         while (@row = $sth->fetchrow_array) {  # retrieve one row at a time
             print join(", ", @row), "\n";
         }
    };
    if ($@) {
        print "$@\n";
        print Dumper($sth->{ParamValues});
    }
 }