PyQT5 QtSql模型未加载数据

Question

使用QtSql库，我试图通过QSqlTableModel将数据加载到QTableView中。但是，当我在模型上调用select（）方法时，模型中没有数据：

from PyQt5.QtCore import Qt, QSize
from PyQt5.QtSql import *
from PyQt5.QtWidgets import QWidget, QTableView, QPushButton, QVBoxLayout


class SclDataBrowse(QWidget):
    def __init__(self, parent=None):
        super(SclDataBrowse, self).__init__(parent)
        self.resize(336, 462)
        self.setup_ui()
        self.setup_db()
        self.setup_model()
        self.view.setModel(self.model)
        if self.db.isOpen():
            self.load_data()

    def setup_ui(self):
        self.layout = QVBoxLayout(self)
        self.view = QTableView(self)
        self.btn_New = QPushButton(self)
        self.btn_New.setMinimumSize(QSize(70, 21))
        self.btn_New.setMaximumSize(QSize(70, 21))
        self.btn_New.setText('New')
        self.layout.addWidget(self.view)
        self.layout.addWidget(self.btn_New)

    def setup_db(self):
        self.db = QSqlDatabase("QMYSQL")
        self.db.setHostName(myhost)
        self.db.setUserName(myuser)
        self.db.setPassword(mypassword)
        self.db.setDatabaseName(mydb)
        self.db.open()

    def setup_model(self):
        self.model = QSqlTableModel(self)
        self.model.setTable("scldata")
        self.model.setEditStrategy(QSqlTableModel.OnManualSubmit)
        self.model.setHeaderData(0, Qt.Horizontal, 'ID')
        self.model.setHeaderData(1, Qt.Horizontal, 'Foreign ID')
        self.model.setHeaderData(2, Qt.Horizontal, 'Receipts Start')
        self.model.setHeaderData(3, Qt.Horizontal, 'Receipts End')
        self.model.setHeaderData(4, Qt.Horizontal, 'Billing Rate')

    def load_data(self):
        print('Loading Data')
        self.model.select()
        print(self.model.rowCount())

我这里缺少什么吗？