如何使用QComboBox中的值编辑数据库（PyQt，Sqlite3，Python）

Question

当数据只是文本时，我有一个编辑数据的系统。我添加了一个组合框，我希望其中的数据也可以编辑。更改组合框并单击编辑按钮后，我希望数据在数据库中更新。我怎么做？ 这是我输出的一个查询的代码。

def click_btn_lessons(self):
    self.screen_name = "lessons"
    self.page_constants()
    self.cur.execute("SELECT StudentID FROM StudentProfile")
    students_students = self.cur.fetchall()
    self.cur.execute("SELECT StudentID FROM Lessons")
    students_lessons = self.cur.fetchall()
    self.cur.execute("""SELECT s.studentID, s.FullName, l.LessonDate, r.RoadExerciseName, e.Rating
                        FROM StudentProfile s
                        LEFT JOIN Lessons l ON s.StudentID=l.StudentID
                        LEFT JOIN LessonExercises e ON l.LessonID=e.LessonID
                        LEFT JOIN RoadExerciseInfo r ON r.RoadExerciseID=e.RoadExerciseID
                        """)
    self.all_data = self.cur.fetchall()

    """This section just removes black records"""
    for student in students_students:
        if student not in students_lessons:
            for item in self.all_data:
                if item[0] == student[0]:
                    self.all_data.remove(item)

    self.table.setRowCount(len(self.all_data))
    self.tableFields = ['check','Full name','Lesson date', 'Exercise', "Rating"]
    self.table.setColumnCount(len(self.tableFields))
    self.table.setHorizontalHeaderLabels(self.tableFields)
    self.checkbox_list = []
    for i, item in enumerate(self.all_data):
        FullName = QtGui.QTableWidgetItem(str(item[1]))
        LessonDate = QtGui.QTableWidgetItem(str(item[2]))
        RoadExerciseName = QtGui.QTableWidgetItem(str(item[3]))

        #This is the combobox and its items
        Rating = QtGui.QComboBox()
        for num in range(5):
            Rating.addItem(str(num))

        self.table.setItem(i, 1, FullName)
        self.table.setItem(i, 2, LessonDate)
        self.table.setItem(i, 3, RoadExerciseName)

        #here is how the combobox isadded to the table
        self.table.setCellWidget(i, 4, Rating)

        #the checkbox items have to be ticked for them to be passed to the edit function
        chkBoxItem = QtGui.QTableWidgetItem()
        chkBoxItem.setFlags(QtCore.Qt.ItemIsUserCheckable | QtCore.Qt.ItemIsEnabled)
        chkBoxItem.setCheckState(QtCore.Qt.Unchecked)
        self.checkbox_list.append(chkBoxItem)
        self.table.setItem(i, 0, self.checkbox_list[i])
        FullName.setFlags(FullName.flags() & ~Qt.ItemIsEditable)
        RoadExerciseName.setFlags(RoadExerciseName.flags() & ~Qt.ItemIsEditable)
    self.name = None
    self.changed_items = []
    self.table.itemChanged.connect(self.log_change)

def log_change(self, item):
    self.table.blockSignals(True)
    item.setBackgroundColor(QtGui.QColor("red"))
    self.table.blockSignals(False)
    self.changed_items.append(item)

def click_btn_edit(self):
    print("Updating")
    for item in self.changed_items:
        self.table.blockSignals(True)
        item.setBackgroundColor(QtGui.QColor("white"))
        self.table.blockSignals(False)
        text, col, row = item.text(), item.column(), item.row()
        new_data = self.all_data
        for i, record in enumerate(self.all_data):
            if i == row:
                if self.checkbox_list[i].checkState() == QtCore.Qt.Checked:
                    #Below adds the new data to the database. 
                    self.cur.execute("""UPDATE {0} SET {1} = ? WHERE {2} = ?""".format(self.table_edit_name,self.columnList[col],self.field_ID),(text,record[0],))

                    """self.field_ID is the field name for the primary key, record[0]. This ensures data is entered in the correct record. 
                    columnList is a list of columns in the record, in order.
                    self.table_edit_name is the name of the table involved."""