my $var_with_chars = "a string";
my @result = [];
        $sql = 'call register_hit(?, @hit_count)';
        #watch out for the "@"!
        my $sth = $db_handle->prepare($sql);
        $sth->execute($var_with_chars) || die $DBI::errstr;
        $sth->finish; 
        # Now get the output variable
        @result = $db_handle->selectrow_array('SELECT @hit_count'); 
        # || die $DBI::errstr;
        print "result=", $result[0], "\n";