the method named "select()" of QSqlTableModel

when i use the method as follows, i find that sometimes select() return false and the next methods can still
work! who knows why or any tips?
Thanks very much!

Code:

---

for()
{
    ...
    QSqlTableModel model;
    model->setEditStrategy(QSqlTableModel::OnManualSubmit);
    model.setTable("tableA");
    model.select();
    model.insertRow(0);
    ...
    model.submitAll();
}

---

anybody knows？

What is the problem exactly? That something works? :)