sub LIMIT_CLAUSE {
    my($self,$limit_clause) = @_;
#    $limit_clause = trim($limit_clause);
    $limit_clause =~ s/^\s+//;
    $limit_clause =~ s/\s+$//;

    return 1 if !$limit_clause;
    my($offset,$limit,$junk) = split /,/, $limit_clause;
    return $self->do_err('Bad limit clause!')
         if (defined $limit and $limit =~ /[^\d]/)
         or ( defined $offset and $offset =~ /[^\d]/ )
         or defined $junk;
    if (defined $offset and !defined $limit) {
        $limit = $offset;
        undef $offset;
    }
    $self->{"struct"}->{"limit_clause"} = {
        limit  => $limit,
        offset => $offset,
     };
     return 1;
}