+sub postattackgroups : Local {
+ my ( $self, $c ) = @_;
+ my $dbh = $c->model;
+
+ my @groups = $c->req->param('class');
+ $dbh->do(q{DELETE FROM groupmembers WHERE gid IN ('x','y','z') AND gid <> ALL($1) AND uid = $2
+ },undef, \@groups, $c->user->id);
+
+ $dbh->do(q{INSERT INTO groupmembers (uid,gid) (
+ SELECT $2, gid FROM unnest($1::text[]) AS gid WHERE gid IN ('x','y','z')
+ EXCEPT
+ SELECT uid,gid FROM groupmembers WHERE uid = $2
+ )},undef, \@groups, $c->user->id);
+
+ $c->res->redirect($c->uri_for(''));
+}
+