C++ (Qt)
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
    db.setDatabaseName("test.db");
    if (!db.open())
    {
        QMessageBox::critical(0, qApp->trUtf8("Cannot open database"),
        qApp->trUtf8("Unable to establish a database connection.\n"
        "Click Close to exit."), QMessageBox::Close);
        return false;
    }
    Dialog w;
    w.show();
    return a.exec();
}