My colleague found a next problem with QSqlTableModel:
Qt Code: 
  1. #define VARIANT_1
  2. class SomeClass : public QWidget
  3. {
  4.     Q_OBJECT
  5.  
  6. public:
  7.  
  8. SomeClass(QWidget *parent = 0, Qt::WFlags flags = 0)
  9. {
  10.     ui.setupUi(this);    
  11.  
  12.     db = QSqlDatabase::addDatabase("QSQLITE");
  13.     db.setDatabaseName(":memory:");
  14.     if (!db.open()) {
  15.         return;
  16.     }
  17.  
  18.     QSqlQuery query;
  19.     query.exec("create table person (id int primary key, "
  20.                "firstname varchar(20), lastname varchar(20))");
  21.     query.exec("insert into person values(101, 'Danny', 'Young')");
  22.     query.exec("insert into person values(102, 'Christine', 'Holand')");
  23.  
  24. #if defined( VARIANT_1 )
  25.     p_model = new QSqlTableModel( );
  26.     QSqlTableModel & model = *p_model;
  27. #endif
  28.     model.setTable("person");
  29.     model.setEditStrategy(QSqlTableModel::OnManualSubmit);
  30.     model.select();
  31.  
  32.     model.setHeaderData(0, Qt::Horizontal, QObject::tr("ID"));
  33.     model.setHeaderData(1, Qt::Horizontal, QObject::tr("First name"));
  34.     model.setHeaderData(2, Qt::Horizontal, QObject::tr("Last name"));
  35.  
  36.     ui.tableView->setModel(&model);
  37.  
  38. }
  39.  
  40. private:
  41.     Ui::qhlbClass ui;
  43. #if defined( VARIANT_1 )
  44.     QSqlTableModel * p_model;
  45. #else
  47. #endif
  48. };
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if VARIANT_1 is defined tableView shows a right table, else - not.
I.e. if QSqlTableModel comes as an object table doesn't shows it's data...
If QSqlTableModel comes as a pointer it's works fine...
Can you comment this ?