typedef boost::tuple<dbo::ptr<Post>, int> Item;
dbo::QueryModel<Item> *model = new dbo::QueryModel<Item>();
model->setQuery(session.query<Item>
("select Post, count(Comment.id) "
"from post Post join comment Comment on Comment.post_id = Post.id")
.where("Post.state = ?").bind(Post::Published)
.groupBy("Post"));
model->addColumn("Post.date");
model->addColumn("Post.title");
model->addColumn("count(Comment.id)");
WTableView *view = new WTableView();
view->resize(600, 300);
view->setSelectionMode(SingleSelection);
view->setModel(model);