my $attr = { Columns => [] };
my $mids = $dbh->selectall_arrayref(<<'', $attr, $$beg, $end);
SELECT num,mid FROM msgmap WHERE num >= ? AND num <= ?
my $attr = { Columns => [] };
my $mids = $dbh->selectall_arrayref(<<'', $attr, $$beg, $end);
SELECT num,mid FROM msgmap WHERE num >= ? AND num <= ?