... (line 762 and further of linkwatcher.pl)
                $query="INSERT INTO $settings{'mysqltableprefix'}linklog (edit_id,lang,pagename,namespace,diff,revid,oldid,wikidomain,user,fullurl,domain,indexedlink) VALUES (";
                $query .= $mysql->quote($edit_id) . ",";
                $query .= $mysql->quote($lang) . ",";
                $query .= $mysql->quote($pagename) . ",";
                $query .= $mysql->quote($namespace) . ",";
                $query .= $mysql->quote($diffurl) . ",";
                $query .= $mysql->quote($revid) . ",";
                $query .= $mysql->quote($oldid) . ",";
                $query .= $mysql->quote($wikidomain) . ",";
                $query .= $mysql->quote($username) . ",";
                $query .= $mysql->quote($thislink) . ",";
                $query .= $mysql->quote($domain) . ",";
                $query .= $mysql->quote($index) . ")";
                print ("QUERY: $query\n");
                &query($query);
...


... (line 826 and further of linkwatcher.pl)
sub query {
    my $query=shift;
    print ("QR: $query\n");
    if ( $query !~ m/^select/i ) {
        my $status = 0;
        eval {
            my $status=$mysql->do($query);
        };
        if ($@) {
            return -1;
        } else {
            return $status;
        }
    } else {
        my $query_handle=$mysql->prepare($query);
        $query_handle->execute;
        my $results=$query_handle->fetchall_arrayref( {} );
        if ( $query_handle->rows > 0 ) {
            return $results;
        } else {
            return undef;
        }
    }
}