my $sql = "SELECT this, that, the_other FROM table WHERE foo = $bar";

my @rows;
my $sth;
my $ratchet_counter = 1;

if  ( $sth = $dbh->prepare($sql) ) {
	$sth->execute();
	while ( @rows = $sth->fetchrow_array() ) {
		
		# Load in new values from current row.
		( $this, $that, $the_other) = @rows;
		
		# Redefine button subs temporarily.
		local *callback_X = sub { ++$ratchet_counter; };    # User wanting next row.
		local *callback_Y = sub { $ratchet_counter = 0; };  # User choosing current row.
			
		$mw->waitVariable(\$ratchet_counter);               # User making choice of show-next or keep-this.
		
		last if 0 == $rows_ratchet_index; # User made choice.
	}
} else {
	$wgt->{'frame'}->{'entry'} = qq|Oops! $DBI::errstr!|;
	return ();
}