数据库版的学生管理系统

import MySQLdb #导入MySQL模块

class Student: #创建student类
    def __init__(self):
        self.db = None
        self.cursor = None
        self.connect() #链接数据库

    def connect(self):
        self.db = MySQLdb.connect(host = \'localhost\',user = \'root\',passwd = \'123456\',db = \'student_1\')
        self.cursor = self.db.cursor()

    def start(self):#主菜单
        while True:
            self.menu1()
            num = raw_input(\'请输入要选择的功能：\')
            print num.isdigit()
            if num.isdigit() == False:
                continue
            num = int(num)
            if num == 1:
                self.showStudent()
            elif num == 2:
                self.addStudent()
            elif num == 3:
                self.delStudent()
            elif num == 4:
                self.updateStudent()
            elif num == 5:
                print \'已成功退出系统\'
                self.close()
                break

    def showStudent(self):#查看学生
        while True:
            self.menu2()
            num = input(\'请选择功能：(0—3)\')
            if num == 1:
                print \'ID 姓名 年龄 性别\'
                self.cursor.execute(\'select * from student\')
                for i in self.cursor.fetchall():
                    print i[0],i[1],i[2],i[3]
            elif num == 2:
                sid = input(\'请输入要查询的ID：\')
                self.cursor.execute(\'select * from student where id = %d\'%sid)
                if self.cursor.rowcount == 0:
                    print \'没有相关学生\'
                else:
                    print \'ID 姓名 年龄 性别\'
                    for i in self.cursor:
                        print i[0],i[1],i[2],i[3]
            elif num == 3:
                sname = raw_input(\'请输入姓名：\')
                self.cursor.execute("select * from student where name = \'%s\'"%sname)
                if self.cursor.rowcount == 0:
                    print \'没有相关学生\'
                else:
                    print \'ID 姓名 年龄 性别\'
                    for i in self.cursor.fetchall():
                        print i[0],i[1],i[2],i[3]
            else:
                self.start()
                break

    def addStudent(self):#添加学生
        while True:
            sname = raw_input(\'请输入学生的姓名：\')
            sage = raw_input(\'请输入学生的年龄：\')
            ssax = raw_input(\'请输入学生的性别：\')
            try:
                sql = \'insert into student(name,age,sax) values(%s,%s,%s)\'
                self.cursor.execute(sql,(sname,sage,ssax))
                self.db.commit()
                print \'添加数据库成功\'
            except:
                self.db.rollback()
                print \'添加数据库失败\'
            q = raw_input(\'任意键继续，Q键退出\').lower()
            if q == \'q\':
                break

    def delStudent(self):#删除学生
        self.menu3()
        num = input(\'请选择需要的功能：\')
        if num == 1:
            sid = raw_input(\'请输入一个ID或者一组ID：\')
            list1 = sid.split(\' \')
            print list1
            list2 = map(lambda x:(int(x),),list1)
            print list2
            sql =\'delete from student where id =%s\'
            try:
                self.cursor.executemany(sql,list2)
                self.db.commit()
                print \'删除成功\'
            except:
                print \'删除失败\'
                self.db.rollback()
        elif num == 2:
            sname = raw_input(\'请输入要删除的学生姓名：\')
            try:
                self.cursor.execute("delete from student where name =\'%s\'"%sname)
                self.db.commit()
                print \'删除成功！\'
            except:
                print \'删除失败！\'
                self.db.rollback()
        else:
            pass

    def updateStudent(self):#修改学生信息
        sid = input(\'请输入要修改的ID：\')
        sname = raw_input(\'请输入新的姓名：\')
        sage = raw_input(\'请输入新的年龄：\')
        ssax = raw_input(\'请输入新的性别：\')
        try:
            self.cursor.execute("update student set name=\'%s\',age=%s,sax=\'%s\' where id = %s"%(sname,sage,ssax,sid))
            self.db.commit()
            print \'修改成功！\'
        except:
            print \'修改失败！\'
            self.db.rollback()

    def menu1(self):
        print """
        ---------------学生管理系统---------------
                        1 查询学生
                        2 添加学生
                        3 删除学生
                        4 修改学生
                        5 退出系统
        ------------------------------------------
        """

    def menu2(self):
        print """
        ----------查询学生----------
                0 返回主菜单
                1 查询所有学生
                2 按ID查询
                3 按姓名查询
        ----------------------------
        """
    def menu3(self):
        print """
        ----------删除学生----------
        0 返回主菜单
        1 按ID删除
        2 按姓名删除
        """

    def close(self):
        self.db.close()

if __name__ == \'__main__\':
    student =Student()
    student.start()