use DBI;
my $dbh = DBI->connect("dbi:mysql:database", "user", "password",
  { RaiseError => 1 });
$dbh->do("SET OPTION SQL_BIG_TABLES = 1"); # for mysql

my $sth = $dbh->prepare(<<'_END');
SELECT
  field1, field2, sum(field3) as Total
FROM some_database
WHERE field2 LIKE 'random%' AND field1 BETWEEN ? and ?
GROUP BY field1, field2
ORDER BY Total DESC
_END

$sth->execute('a', 'k');
$sth->bind_columns(\my($field1, $field2, $sum));

while ($sth->fetch) {
   printf "%20s %20s %s\n", $field1, $field2, $sum;
}

$sth->finish;
$dbh->disconnect;