问题是，如果在用户名行编辑或密码行编辑中写入任何单词，则显示登录正确。。。我只想要数据库中注册了数据的raect。。
im在mysql中创建数据库： def page_login(self): im为用户名和密码创建了检查字段： def checkfiels(self): （如果留下用户名或密码或两个空字段或填写标签user和pasword，则无需连接数据库即可正常工作。完成！！
我现在希望如果数据库中已填充标签用户或密码，则显示来自以下位置的消息错误： def checkfiels(self): 这里有一个代码：

from cgitb import enable
    from peewee import *
    import self
    from PyQt5.QtCore import QPropertyAnimation
    from PySide2 import *
    from PyQt5 import *
    import Resources_rc
    from PyQt5 import QtCore, QtGui, QtWidgets, uic
    from PyQt5.QtWidgets import QPushButton, QLineEdit
    import sys
    import pymysql

    pymysql.install_as_MySQLdb()

    class MyWindow(QtWidgets.QMainWindow):
        def __init__(self, maxWidth=None):
            super(MyWindow, self).__init__()
            self.mysql_db = MySQLDatabase('data', user='root', password='toor', host='127.0.0.1', port=3306)
            uic.loadUi('MainWindow.ui', self)
            self.handel_buttons()
            self.db_connection()
            self.add_users()

            self.frame_error.hide()  
            self.btn_close_popup_7.clicked.connect(lambda: self.frame_error.hide())
            self.btn_log_6.clicked.connect(self.checkfiels)

    ######################## CONNECT DATABASE ##################
        def db_connection(self):
            self.cur = self.mysql_db.cursor()
            print('connected')

    ######################## FORM LOGIN  ##################

        def page_login(self):
            username = self.lineEdit_10.text()
            password = self.lineEdit_5.text()

            self.cur.execute(''' SELECT username , password FROM users''')
            data = self.cur.fetchall()
            found = True
            for row in data:

                if row[0] == username and row[1] == password:
                    self.frame_left_menu.show()
                    print(row)

    ######################## CHECK FIELS FORM LOGIN #######

        def checkfiels(self):

            textUser = " "
            textPassword = " "

            def showMessage(message):
                self.frame_error.show()
                self.label_164.setText(message)

            ## CHECK USER ##
            if not self.lineEdit_10.text():
                textUser = " User Empty "
            else:
                textUser = ""

            ## CHECK PASSWORD ##
            if not self.lineEdit_5.text():
                textPassword = " Password Empty "
            else:
                textPassword = ""

            if textUser + textPassword != '':
                text = textUser + textPassword
                showMessage(text)
            else:
                text = " Login OK. "   
                if self.checkBox_6.isChecked():
                    text = text + " | Saver User OK. "
                showMessage(text)

    if __name__ == '__main__':
        app = QtWidgets.QApplication(sys.argv)
        window = MyWindow()
        window.show()
        sys.exit(app.exec_())

非常感谢。