mysql数据库：

create table student
(
sno varchar(10) primary key ,
sname varchar(20) not null unique,
ssex char(3) check(ssex in('男','女')),
sage smallint not null,
pwd varchar(20) not null
);

create table teacher
(
tno varchar(7) primary key,
tname varchar(20) not null unique,
tposition varchar(20) not null,
tsalary smallint not null,
pwd varchar(20) not null
);

create table course
(
cno varchar(4) primary key,
cname varchar(40) not null unique,
ccredit smallint not null,
tno varchar(7) not null,
foreign key (tno) references teacher(tno)
);
create table sc
(
sno varchar(10) not null,
cno varchar(4) not null,
grade smallint not null,
primary key(sno,cno),
foreign key (sno) references student(sno),
foreign key (cno) references course(cno)
);
create table syscontroler
(
kno varchar(10) primary key,
kname varchar(20) not null unique,
klevel enum('一','二','三')
);

insert into student(sname,ssex,sno, sage, pwd) values('李天明','男','2006100067',21,'123456');
insert into student(sname,ssex,sno, sage, pwd) values('陈小红','女','2006100068',19,'123456');
insert into student(sname,ssex,sno, sage, pwd) values('王明白','女','2006100069',18,'123456');
insert into student(sname,ssex,sno, sage, pwd) values('张小黑','男','2006100070',19,'123456');
insert into student(sname,ssex,sno, sage, pwd) values('林与','男','2006100071',21,'123456');


insert into teacher(tno,tname, tposition, tsalary, pwd) values('t001','李杰出','教授',8000,'123456');
insert into teacher(tno,tname, tposition, tsalary, pwd) values('t002','郑好','专任教师',5000,'123456');
insert into teacher(tno,tname, tposition, tsalary, pwd) values('t003','刘光明','教授',7000,'123456');
insert into teacher(tno,tname, tposition, tsalary, pwd) values('t004','何小兵','副教授',6000,'123456');
insert into teacher(tno,tname, tposition, tsalary, pwd) values('t005','黄小白','副教授',6500,'123456');
insert into teacher(tno,tname, tposition, tsalary, pwd) values('t006','林峰地','教授',7500,'123456');

insert into course values('6','高等数学',6,'t003');
insert into course values('2','计算机组成原理',3,'t004');
insert into course values('7','java语言',4,'t003');
insert into course values('5','操作系统',3,'t005');
insert into course values('1','数据库',2,'t001');
insert into course values('3','计算机网络',4,'t002');
insert into course values('4','数据结构',5,'t002');

insert into sc values('2006100067','1',92);
insert into sc values('2006100068','2',85);
insert into sc values('2006100069','4',88);
insert into sc values('2006100070','2',90);
insert into sc values('2006100071','5',80);

insert into syscontroler(kno,kname,klevel) values('t002','郑好','三');
insert into syscontroler(kno,kname,klevel) values('t001','李杰出','二');
insert into syscontroler(kno,kname,klevel) values('t003','刘光明','二');
insert into syscontroler(kno,kname,klevel) values('t006','林峰地','二');
insert into syscontroler(kno,kname,klevel) values('t004','何小兵','一');
insert into syscontroler(kno,kname,klevel) values('t005','黄小白','一');
insert into syscontroler(kno,kname,klevel) values('2006100067','李天明','一');
insert into syscontroler(kno,kname,klevel) values('2006100068','陈小红','一');
insert into syscontroler(kno,kname,klevel) values('2006100069','王明白','一');

create view courseinfo as select course.cno 课程编号,course.cname 课程名称,teacher.tname 任课老师,course.ccredit 课程学分,countnum 选修人数,
avg_grade 平均分,max_grade 最高分,min_grade 最低分 from teacher,
course left outer join (select cname, count(*) countnum,avg(grade) avg_grade,max(grade) max_grade,min(grade) min_grade from sc,course 
where course.cno=sc.cno group by cname)a1 on (course.cname=a1.cname) where teacher.tno=course.tno;

create view studentinfo as select student.sno 学号,student.sname 姓名,(select sum(grade) from sc where sno=student.sno) 总分 ,
(select sum(ccredit) from course where cno in (select cno from sc where sno=student.sno)) 总学分 ,
(select max(grade) from sc where sc.sno in (student.sno)) 最高分,(select min(grade) from sc where sc.sno in (student.sno)) 最低分 from student;

create view teacherinfo1 as select tposition 职位,count(tno) 在任人数,avg(tsalary) 平均工资 from teacher group by tposition;

create view teacherinfo2 as select tno 教师工号,tname 教师名称,(select count(student.sno) from student,sc,course where student.sno=sc.sno and sc.cno=course.cno and course.tno=teacher.tno) 授课学生总人数 from teacher;
Commit;

第一次搞没什么经验，用navicat把mysql数据库里的表导出后，再重新导入新创建的.db文件中

python主要通过sqlite3

import sqlite3


def opendb():  # 打开数据库
    conn = sqlite3.connect('C://D-drive-103625//Ubantu//datebase_e.db')
    cur = conn.execute(" ")
    return cur, conn


def show_student_db():  # 打印学生信息表
    print("--------------------学生信息表--------------------")
    hel = opendb()
    cur = hel[1].cursor()
    cur.execute("SELECT * FROM student")
    res = cur.fetchall()
    for line in res:
        print(line)
    cur.close()


def show_course_db():  # 打印课程信息表
    print("--------------------课程信息表--------------------")
    hel = opendb()
    cur = hel[1].cursor()
    cur.execute("SELECT * FROM course")
    res = cur.fetchall()
    for line in res:
        print(line)
    cur.close()


def show_teacher_db():  # 打印教师信息表
    print("--------------------教师信息表--------------------")
    hel = opendb()
    cur = hel[1].cursor()
    cur.execute("SELECT * FROM teacher")
    res = cur.fetchall()
    for line in res:
        print(line)
    cur.close()


def show_sc_db():  # 打印成绩信息表
    print("--------------------成绩信息表--------------------")
    hel = opendb()
    cur = hel[1].cursor()
    cur.execute("SELECT * FROM sc")
    res = cur.fetchall()
    for line in res:
        print(line)
    cur.close()


def show_syscontroler_db():  # 打印管理员信息表
    print("--------------------管理员信息表--------------------")
    hel = opendb()
    cur = hel[1].cursor()
    cur.execute("SELECT * FROM syscontroler")
    res = cur.fetchall()
    for line in res:
        print(line)
    cur.close()


def input_info(n):  # 插入新数据
    while n == 1:  # 插入学生数据
        sno = input("请输入学号:")
        sname = input("请输入姓名:")
        ssex = input("请输入性别:")
        sage = input("请输入年龄:")
        pwd = input("请输入简介：")
        return sno, sname, ssex, sage, pwd
    while n == 2:  # 插入教师数据
        tno = input("请输入教师编号:")
        tname = input("请输入姓名:")
        tposition = input("请输入职称:")
        tsalary = input("请输入每月薪资:")
        pwd = input("请输入简介：")
        return tno, tname, tposition, tsalary, pwd
    while n == 3:  # 插入课程数据
        cno = input("请输入课程编号:")
        cname = input("请输入课程名:")
        ccredit = input("请输入学分:")
        tno = input("请输入授课教师编号:")
        return cno, cname, ccredit, tno
    while n == 4:  # 插入成绩数据
        sno = input("请输入学生学号:")
        cno = input("请输入课程编号:")
        grade = input("请输入成绩:")
        return sno, cno, grade
    while n == 5:  # 插入管理员信息
        kno = input("请输入学生学号:")
        kname = input("请输入课程编号:")
        klevel = input("请输入成绩:")
        return kno, kname, klevel


#  print("数据成功插入！")


def add_to_db(n):  # 向表中添加新的数据
    print("--------------------欢迎使用添加数据功能--------------------")
    while n == 1:  # 添加学生数据
        print("--------------------请输入需要添加的数据--------------------")
        in_data = input_info(1)
        hel = opendb()
        hel[1].execute("insert into student(sname,ssex,sno, sage, pwd) values(?,?,?,?,?)",
                       (in_data[0], in_data[1], in_data[2], in_data[3]), in_data[4])
        hel[1].commit()
        print("--------------------数据添加成功！--------------------")
        show_student_db()
        hel[1].close()
    while n == 2:  # 添加教师数据
        print("--------------------请输入需要添加的数据--------------------")
        in_data = input_info(2)
        hel = opendb()
        hel[1].execute("insert into teacher(tno,tname, tposition, tsalary, pwd) values (?,?,?,?,?)",
                       (in_data[0], in_data[1], in_data[2], in_data[3]), in_data[4])
        hel[1].commit()
        print("--------------------数据添加成功！--------------------")
        show_teacher_db()
        hel[1].close()
    while n == 3:  # 添加课程数据
        print("--------------------请输入需要添加的数据--------------------")
        in_data = input_info(3)
        hel = opendb()
        hel[1].execute("insert into course values (?,?,?,?)",
                       (in_data[0], in_data[1], in_data[2], in_data[3]))
        hel[1].commit()
        print("--------------------数据添加成功！--------------------")
        show_course_db()
        hel[1].close()
    while n == 4:  # 添加成绩数据
        print("--------------------请输入需要添加的数据--------------------")
        in_data = input_info(4)
        hel = opendb()
        hel[1].execute("insert into sc values(?,?,?,?)",
                       (in_data[0], in_data[1], in_data[2], in_data[3]))
        hel[1].commit()
        print("--------------------数据添加成功！--------------------")
        show_sc_db()
        hel[1].close()
    while n == 5:  # 添加管理员信息
        print("--------------------请输入需要添加的数据--------------------")
        in_data = input_info(5)
        hel = opendb()
        hel[1].execute("insert into syscontroler(kno,kname,klevel) values(?,?,?)",
                       (in_data[0], in_data[1], in_data[2]))
        hel[1].commit()
        print("--------------------数据添加成功！--------------------")
        show_syscontroler_db()
        hel[1].close()


def del_db(n):  # 删除表中的某项数据
    print("--------------------欢迎使用删除数据功能--------------------")
    while n == 1:
        print("--------------------删除学生信息--------------------")
        del_choice = input("请输入想要删除的学号")
        hel = opendb()  # 返回游标conn
        hel[1].excute("delete from student where sno =" + del_choice)
        hel[1].commint()
        print("--------------------数据删除成功！--------------------")
        show_student_db()
        hel[1].close
    while n == 2:
        print("--------------------删除教师信息--------------------")
        del_choice = input("请输入想要删除的教职工号")
        hel = opendb()  # 返回游标conn
        hel[1].excute("delete from teacher where tno =" + del_choice)
        hel[1].commint()
        print("--------------------数据删除成功！--------------------")
        show_teacher_db()
        hel[1].close
    while n == 3:
        print("--------------------删除课程信息--------------------")
        del_choice = input("请输入想要删除的课程号")
        hel = opendb()  # 返回游标conn
        hel[1].excute("delete from course where cno =" + del_choice)
        hel[1].commint()
        print("--------------------数据删除成功！--------------------")
        show_course_db()
        hel[1].close
    while n == 4:
        print("--------------------删除成绩信息--------------------")
        del_choice = input("请输入想要删除成绩的学生的学号")
        hel = opendb()  # 返回游标conn
        hel[1].excute("delete from sc where sno =" + del_choice)
        hel[1].commint()
        print("--------------------数据删除成功！--------------------")
        show_sc_db()
        hel[1].close
    while n == 5:
        print("--------------------删除管理员信息--------------------")
        del_choice = input("请输入想要删除的账号")
        hel = opendb()  # 返回游标conn
        hel[1].excute("delete from syscontroler where kno =" + del_choice)
        hel[1].commint()
        print("--------------------数据删除成功！--------------------")
        show_syscontroler_db()
        hel[1].close


def alter_db(n):  # 修改表中已存在的数据
    print("--------------------欢迎使用修改数据功能--------------------")
    while n == 1:
        print("--------------------学生数据修改--------------------")
        alter_choice = input("请输入想要修改学生的学号")
        hel = opendb()
        person = input_info(1)
        hel[1].execute("update student set sno=?,sname=?,ssex=?,sage=?,pwd=? where sno = " + alter_choice,
                       (person[0], person[1], person[2], person[3]))
        hel[1].commint()
        show_student_db()
        hel[1].close()
    while n == 2:
        print("--------------------教师数据修改--------------------")
        alter_choice = input("请输入想要修改的教师的职工号")
        hel = opendb()
        person = input_info(2)
        hel[1].execute(
            "update teacher set tno=?,tname=?,tposition=?,tsalary=?,pwd=? where tno = " + alter_choice,
            (person[0], person[1], person[2], person[3]))
        hel[1].commint()
        show_student_db()
        hel[1].close()
    while n == 3:
        print("--------------------课程数据修改--------------------")
        alter_choice = input("请输入想要修改课程的课程号")
        hel = opendb()
        person = input_info(3)
        hel[1].execute("update course set cno=?,cname=?,ccredit=?,tno=? where cno = " + alter_choice,
                       (person[0], person[1], person[2], person[3]))
        hel[1].commint()
        show_student_db()
        hel[1].close()
    while n == 4:
        print("--------------------成绩数据修改--------------------")
        alter_choice = input("请输入想要修改成绩的学生学号")
        hel = opendb()
        person = input_info(4)
        hel[1].execute("update sc set sno=?,cno=?,grade=? where sno = " + alter_choice,
                       (person[0], person[1], person[2], person[3]))
        hel[1].commint()
        show_student_db()
        hel[1].close()
    while n == 5:
        print("--------------------成绩数据修改--------------------")
        alter_choice = input("请输入想要修改成绩的学生学号")
        hel = opendb()
        person = input_info(5)
        hel[1].execute("update syscontroler set kno=?,kname=?,klevel=? where kno = " + alter_choice,
                       (person[0], person[1], person[2], person[3]))
        hel[1].commint()
        show_student_db()
        hel[1].close()


def search_db(n):  # 查询单行数据
    print("--------------------欢迎使用查询数据功能--------------------")
    while n == 1:
        print("--------------------学生数据查询--------------------")
        search_choice = input("请输入要查询学生的学号")
        hel = opendb()
        cur = hel[1].cursor()
        cur.execute("select * from student where sno=" + search_choice)
        hel[1].commit()
        print("--------------------你所查找的数据如下--------------------")
        res = cur.fetchall()
        for line in res:
            print(line)
        cur.close()
        hel[1].close()
    while n == 2:
        print("--------------------教师数据查询--------------------")
        search_choice = input("请输入要查询教师的职工号")
        hel = opendb()
        cur = hel[1].cursor()
        cur.execute("select * from teacher where tno=" + search_choice)
        hel[1].commit()
        print("--------------------你所查找的数据如下--------------------")
        res = cur.fetchall()
        for line in res:
            print(line)
        cur.close()
        hel[1].close()
    while n == 3:
        print("--------------------课程数据查询--------------------")
        search_choice = input("请输入要查询课程的课程号")
        hel = opendb()
        cur = hel[1].cursor()
        cur.execute("select * from course where cno=" + search_choice)
        hel[1].commit()
        print("--------------------你所查找的数据如下--------------------")
        res = cur.fetchall()
        for line in res:
            print(line)
        cur.close()
        hel[1].close()
    while n == 4:
        print("--------------------成绩数据查询--------------------")
        search_choice = input("请输入要查询学生成绩的学号")
        hel = opendb()
        cur = hel[1].cursor()
        cur.execute("select * from sc where sno=" + search_choice)
        hel[1].commit()
        print("--------------------你所查找的数据如下--------------------")
        res = cur.fetchall()
        for line in res:
            print(line)
        cur.close()
        hel[1].close()
    while n == 5:
        print("--------------------管理员数据查询--------------------")
        search_choice = input("请输入要查询管理员帐号")
        hel = opendb()
        cur = hel[1].cursor()
        cur.execute("select * from syscontroler where kno=" + search_choice)
        hel[1].commit()
        print("--------------------你所查找的数据如下--------------------")
        res = cur.fetchall()
        for line in res:
            print(line)
        cur.close()
        hel[1].close()


def del_table(n):  # 删表
    hel = opendb()
    cur = hel[1].cursor()
    while n == 1:  # 删除学生表
        cur.execute("drop table student")
        show_student_db()
    while n == 2:  # 删除教师表
        cur.execute("drop table teacher")
        show_teacher_db()
    while n == 3:  # 删除课程表
        cur.execute("drop table course")
        show_course_db()
    while n == 4:  # 删除成绩表
        cur.execute("drop table sc")
        show_sc_db()
    while n == 5:  # 删除管理员表
        cur.execute("drop table syscontroler")
        show_syscontroler_db()


if __name__ == "__main__":
    flag1 = 1  # 主菜单循环条件
    while flag1 == 1:     # 初级菜单
        print("--------------------欢迎使用信息管理系统--------------------")
        choice_show1 = """
        请选择操作：
        （添加）        ---A
        （删除）        ---B
        （修改）        ---C
        （查询）        ---D
        （查看现有数据）---E
        （删除整个表）  ---F
        """
        choice1 = input(choice_show1)
        if choice1 == "A":
            flag2 = 1  # 次级菜单循环条件
            while flag2 == 1:  # 次级菜单
                choice_show2 = """
                    请选择您的操作对象：
                    学生        ---A
                    教师        ---B
                    课程        ---C
                    成绩        ---D
                    管理员信息   ---E
                    """
                choice2 = input(choice_show2)
                if choice2 == "A":
                    add_to_db(1)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "B":
                    add_to_db(2)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "C":
                    add_to_db(3)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "D":
                    add_to_db(4)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "E":
                    add_to_db(5)
                    flag2 = int(input("是否继续（0 or 1）？"))
                else:
                    print("输入错误！")
            flag1 = int(input("是否继续（0 or 1）？"))
        elif choice1 == 'B':
            flag2 = 1
            while flag2 == 1:
                choice_show2 = """
                                请选择您的操作对象：
                                学生        ---A
                                教师        ---B
                                课程        ---C
                                成绩        ---D
                                管理员信息   ---E
                                """
                choice2 = input(choice_show2)
                if choice2 == "A":
                    del_db(1)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "B":
                    del_db(2)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "C":
                    del_db(3)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "D":
                    del_db(4)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "E":
                    del_db(5)
                    flag2 = int(input("是否继续（0 or 1）？"))
                else:
                    print("输入错误！")
            flag1 = int(input("是否继续（0 or 1）？"))
        elif choice1 == 'C':
            flag2 = 1
            while flag2 == 1:
                choice_show2 = """
                                          请选择您的操作对象：
                                          学生        ---A
                                          教师        ---B
                                          课程        ---C
                                          成绩        ---D
                                          管理员信息   ---E
                                          """
                choice2 = input(choice_show2)
                if choice2 == "A":
                    alter_db(1)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "B":
                    alter_db(2)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "C":
                    alter_db(3)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "D":
                    alter_db(4)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "E":
                    alter_db(5)
                    flag2 = int(input("是否继续（0 or 1）？"))
                else:
                    print("输入错误！")
            flag1 = int(input("是否继续（0 or 1）？"))
        elif choice1 == 'D':
            flag2 = 1
            while flag2 == 1:
                choice_show2 = """
                                          请选择您的操作对象：
                                          学生        ---A
                                          教师        ---B
                                          课程        ---C
                                          成绩        ---D
                                          管理员信息   ---E
                                          """
                choice2 = input(choice_show2)
                if choice2 == "A":
                    search_db(1)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "B":
                    search_db(2)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "C":
                    search_db(3)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "D":
                    search_db(4)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "E":
                    search_db(5)
                    flag2 = int(input("是否继续（0 or 1）？"))
                else:
                    print("输入错误！")
            flag1 = int(input("是否继续（0 or 1）？"))
        elif choice1 == 'E':
            flag2 = 1
            while flag2 == 1:
                choice_show2 = """
                                          请选择您的操作对象：
                                          学生        ---A
                                          教师        ---B
                                          课程        ---C
                                          成绩        ---D
                                          管理员信息   ---E
                                          """
                choice2 = input(choice_show2)
                if choice2 == "A":
                    show_student_db()
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "B":
                    show_teacher_db()
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "C":
                    show_course_db()
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "D":
                    show_sc_db()
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "E":
                    show_syscontroler_db()
                    flag2 = int(input("是否继续（0 or 1）？"))
                else:
                    print("输入错误！")
            flag1 = int(input("是否继续（0 or 1）？"))
        elif choice1 == 'F':
            flag2 = 1
            while flag2 == 1:
                choice_show2 = """
                                          请选择您的操作对象：
                                          学生        ---A
                                          教师        ---B
                                          课程        ---C
                                          成绩        ---D
                                          管理员信息   ---E
                                          """
                choice2 = input(choice_show2)
                if choice2 == "A":
                    del_table(1)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "B":
                    del_table(2)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "C":
                    del_table(3)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "D":
                    del_table(4)
                    flag2 = int(input("是否继续（0 or 1）？"))
                elif choice2 == "E":
                    del_table(5)
                    flag2 = int(input("是否继续（0 or 1）？"))
                else:
                    print("输入错误！")
            flag1 = int(input("是否继续（0 or 1）？"))
        else:
            print("输入错误！请输入：A|B|C|D|E|F")