PyQt - QTableView doesn't respond dataChanged

QSqlQueryModel is a great database model, but it is read only. So I rewrite its setData() and flags() method. Now, I can edit my database table from QTableView

But QTableView won't refresh itself when I emited a dataChanged(), when I edited a textbox in the QTableView and clicked somewhere else, the new value wrote into the database successfully, but the value of the textbox reverted to the old value. I have to re-select the whole table, got really bad performance...

Why?

class StudentsTableModel(QtSql.QSqlQueryModel):
    def __init__(self):
        QtSql.QSqlQueryModel.__init__(self)
        self.LockedColumns = []

    def flags(self, index):
        flags = QtSql.QSqlQueryModel.flags(self, index)
        if index.column() not in self.LockedColumns:
            flags |= QtCore.Qt.ItemIsEditable
        return flags

    def setData(self, index, value, role):
        primary_key_index = self.index(index.row(), 0)
        name = self.data(primary_key_index)
        field = self.record().fieldName(index.column())
        self.update(name, field, value)

        self.dataChanged.emit(self.index, self.index)

        # Why DataView isn't refresh automatically when
        # a dataChanged signal emited? Force re-select...
        self.select(self.week)

        return True

    def update(self, name, field, value):
        query = QtSql.QSqlQuery()
        sql = ("UPDATE student_info SET '%s' = '%s' WHERE 学生姓名 = '%s'"
                % (field, value, name))
        query.exec(sql)

    def select(self, week):
        self.week = week
        sql = ("SELECT 学生姓名,第%s周,小组 FROM student_info" % (week))
        self.setQuery(sql)

See how if this model works for you:

class sqlTableModel(QSqlTableModel):
    def __init__(self, parent=None):
        super(sqlTableModel, self).__init__(parent)

    def setData(self, index, value, role=Qt.EditRole):
        if role == Qt.EditRole:
            value = value.strip() if type(value) == str else value

        return super(sqlTableModel, self).setData(index, value, role)

    def flags(self, index):
        itemFlags = super(sqlTableModel, self).flags(index)

        if index.column() != 0:
            return itemFlags | Qt.ItemIsEditable

        return itemFlags ^ Qt.ItemIsEditable #  First column not editable

Instead of setQuery, to set the table I would have something like this in the main class:

def setDatabase(self, nameDatabase):
    self.database = QSqlDatabase.addDatabase("QSQLITE")
    self.database.setDatabaseName(nameDatabase)

    return self.database.open()

def setTable(self, nameTable):
    self.model = sqlTableModel(self)
    self.model.setEditStrategy(QSqlTableModel.OnManualSubmit)
    self.model.setTable(nameTable)
    self.model.select()

    self.view.setModel(self.model)

def saveTable(self):
    if self.model.submitAll():
        return True

    self.model.database().rollback()
    return False