在Python中，哪一个比其他的更有效？我的要求是在关闭应用程序之前保持一个连接。
我有两个类，一个是创建和获取连接/游标，并使用它来获取和获取服务中的数据。Python中的MVC：）
一个DBConnection类

import pyodbc

class Connection:
    def getconnection(self):
        conn =  pyodbc.connect('Driver={SQL Server};Server=.\SQLEXPRESS;Database=School;Trusted_Connection=yes;')
        print("Connection Established")
        #cursor = conn.cursor()
        return conn

    def getcursor(self):
        conn = pyodbc.connect('Driver={SQL Server};Server=.\SQLEXPRESS;Database=School;Trusted_Connection=yes;')
        print("Connection Established")
        cursor = conn.cursor()
        return cursor

和一个服务类

import Connection
import pyodbc

class StudentDataService:

    connection = Connection.Connection().getconnection()
    cursor = Connection.Connection().getcursor()

    def getstudentdata(self):
        print("In method getStudentdata()")
        try:
            row = self.connection.execute('select * from StudentGrade')
            studentList = list(row)
            return studentList
        except pyodbc.DatabaseError as err:
            print("Error Occurred while fetching Student Records", err)
            return None
        finally:
            self.connection.close()

    def getcursorstudentdata(self):
        print("In method getcursorstudentdata()")
        try:
            row = self.cursor.execute('select * from StudentGrade')
            studentList = list(row)
            return studentList
        except pyodbc.DatabaseError as err:
            print("Error Occurred while fetching Student Records", err)
            return None
        finally:
            self.cursor.close()

stu = StudentDataService()
print(stu.getstudentdata())
print("++++++++++++++++++++++++++++++++")
print(stu.getcursorstudentdata())

两个都给了我结果

Connection Established
Connection Established
In method getStudentdata()
[(1, 2021, 2, Decimal('4.00')), (2, 2030, 2, Decimal('3.50')),... ]
++++++++++++++++++++++++++++++++
In method getcursorstudentdata()
[(1, 2021, 2, Decimal('4.00')), (2, 2030, 2, Decimal('3.50')),... ]

所以我的困惑是，该用哪一个？