相信大家在学习python编程时绝对离不开数据库的连接，那么我们就用python来连接数据库实现一个简单的图书借阅系统。其实也很简单，就是在我们的程序中加入sql语句即可
数据库的表结构
我们在这里需要三张表，一张用户表，一张图书表和一张借阅表。注意我们的数据库命名为bbs（book borrow system）
1.用户表
2.图书表
bookname:书名
author：作者
booknum：图书编号
bookpress:出版社
bookamoun:图书数量
3.借阅表
id:借阅号
borrowname:借阅人
borrowbook:借阅图书
bookid:图书编号同图书表booknum
borrowamoun:借阅数量
borrowdate:借阅日期
borrowback:归还日期
Python程序
1.主程序：图书借阅系统.py
# _*_ coding:utf-8 _*_
import pymysql
import db_event
import book_manage
while True:
print("欢迎使用图书借阅系统\
[1]登陆 [2]注册 [3]退出")
choice = int(input("请输入您要进行的操作（数字）："))
if choice == 1:
name = input("请输入用户名：")
login_status=db_event.user_login(name)
if login_status==1:
book_manage.manage(name)
else:
print("登陆失败")
continue
elif choice==2:
create_user = db_event.user_create()
print("用户创建成功，您创建的用户信息如下：/n\
姓名：%s 年龄：%d 性别：%s 密码：%s" % (create_user[0], create_user[1], create_user[2], create_user[3]))
elif choice==3:
exit()
else:
print("无效操作！")
continue2.图书的管理信息：book_manage.py
import db_event
def manage(name):
while True:
print("欢迎进入图书系统\n\
[1]查询图书 [2] 借阅图书 [3]捐赠图书 [4]归还图书 [5]退出")
num = int(input('输入您的选择：'))
if num == 1:
db_event.book_select()
elif num == 2 :
chos=int(input("请选择[1]借阅 [2]续借 [3]查询借阅信息 [4]退出"))
if chos==1:
db_event.book_borrow(name)
elif chos==2:
db_event.borrow_again()
elif chos==3:
db_event.borrow_info_select(name)
elif chos==4:
continue
else:
print("无效操作")
elif num == 3 :
db_event.book_juanzeng()
elif num == 4 :
db_event.book_back()
elif num == 5 :
break
else:
print("无效输入！")3.数据库的操作:db_event.py
# _*_ coding:utf-8 _*_
import pymysql
import random
import string
def user_login(name):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "SELECT name,mima FROM user WHERE name='%s'" %(name)
cursor.execute(sql)
results = cursor.fetchall()
if results:
res=results[0]
for i in range(3):
mima = input("请输入密码：")
if mima == res[1]:
print("登陆成功！")
login_status = 1
break
else:
login_status=0
print("密码输入不正确!请重新输入")
# print(login_status)
if login_status == 1 :
return login_status
else:
print("您已输入错误密码三次，无法登陆图书借阅系统，欢迎下次使用！")
login_status = 0
return login_status
else:
login_status = 0
print("您输入的用户不存在！")
return login_status
db.close()
#判断是否登陆成功，1为成功，0为不成功
# login_status=user_login()
# if login_status==1:
# print("ok")
# else:
# print("no")
#关闭数据库连接
# curcor.close()
# db.close()
def user_create():
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
name=input("请输入姓名：")
age=int(input("请输入年龄:"))
sex=input("请输入性别[M]男 [W]女 ：")
mima=input("为您的用户设置一个8位数密码：")
sql = "INSERT INTO user VALUES('%s',%s,'%s','%s')" %(name,age,sex,mima)
cursor.execute(sql)
db.commit()
sql1="SELECT * FROM user WHERE name='%s'" %(name)
cursor.execute(sql1)
results=cursor.fetchone()
return results
db.close()
#create_user=user_create()
#print("用户创建成功，您创建的用户信息如下：/n\
# 姓名：%s 年龄：%d 性别：%s 密码：%s" %(create_user[0],create_user[1],create_user[2],create_user[3]))
def book_info_select(x,y):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "SELECT * FROM book WHERE %s='%s'" %(x,y)
cursor.execute(sql)
results=cursor.fetchone()
if results:
print("书名：%s 作者：%s 书籍编号：%s 出版社：%s 剩余数量：%d " %(results[0],results[1],results[2],results[3],results[4]))
else:
print("没有您所要查询的图书")
db.close()
def book_select():
a = int(input("输入您要查询的图书关键信息\
[1]书名 [2]作者 [3]书籍号 [4]出版社"))
b=""
if a == 1 :
b="bookname"
name=input("请输入要查询的书名：")
book_info_select(b,name)
elif a == 2 :
b="author"
auth=input("请输入作者名：")
book_info_select(b,auth)
elif a == 3 :
b="booknum"
num=input("请输入书籍编号")
book_info_select(b,num)
elif a == 4 :
b="bookpress"
press=input("请输入出版社：")
book_info_select(b,press)
else:
print("输入有误")
book_select()
def gen_code(len=8):
code_str = string.ascii_letters + string.digits
return ''.join(random.sample(code_str, len))
def book_add(name,auth,press,amount):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
num=gen_code()
sql = "INSERT INTO book VALUES('%s','%s','%s','%s',%s)" %(name,auth,num,press,amount)
sql1 = "SELECT booknum FROM book"
cursor.execute(sql1)
res = cursor.fetchall()
list=[]
for i in res :
list.append(i)
try:
while True:
if num in list:
gen_code()
else:
cursor.execute(sql)
db.commit()
print("图书捐赠成功，谢谢您！")
break
except:
print("输入图书数目错误！")
db.rollback()
db.close()
def book_update_add(name,auth,press,amount):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql="UPDATE book SET bookamount=bookamount+%s WHERE bookname='%s' AND author='%s' AND bookpress='%s'" %(amount,name,auth,press)
try:
cursor.execute(sql)
db.commit()
print("图书捐赠成功，谢谢您！")
except:
print("输入图书数目错误！")
db.rollback()
db.close()
def book_juanzeng():
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
name=input("请输入您要捐赠的图书书名：")
auth=input("请输入您要捐赠的图书作者：")
press=input("请输入您要捐赠的图书的出版社：")
amount = int(input("输入您要捐赠的数目："))
sql = "SELECT * FROM book WHERE bookname='%s'AND author='%s' AND bookpress='%s'" %(name,auth,press)
cursor.execute(sql)
results=cursor.fetchone()
if results:
book_update_add(name,auth,press,amount)
else:
book_add(name,auth,press,amount)
db.close()
def book_if_borrow(booknum,amount):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "SELECT bookamount FROM book WHERE booknum='%s'" %(booknum)
cursor.execute(sql)
res = cursor.fetchall()
if res:
if res[0][0] >= amount :
#编号为booknum的书的数量还有，可以借
return True
else:
print("您所需要的编号为%s的书籍当前图书馆只有%d本，不满足您的需求" %(booknum,res[0][0]))
return False
else:
print("查无此书，请确认您的书籍编号！")
return False
db.close()
def book_borrow_after(amount,booknum):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "UPDATE book SET bookamount=bookamount-%s WHERE booknum='%s'" %(amount,booknum)
cursor.execute(sql)
db.commit()
db.close()
def borrow_add(name,booknum,amount):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
days = int(input("请输入您选择借阅的天数（不可超过365天）："))
sql = "INSERT INTO borrow VALUES(NULL,'%s',(SELECT bookname FROM book WHERE booknum='%s'),'%s',%s,CURDATE(),DATE_ADD(CURDATE(),INTERVAL %s DAY))" %(name,booknum,booknum,amount,days)
cursor.execute(sql)
db.commit()
def select_after_borrow(booknum,name):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql2 = "SELECT * FROM borrow WHERE bookid='%s' AND borrowname='%s'" % (booknum, name)
cursor.execute(sql2)
return cursor.fetchall()
def book_borrow(name):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
booknum=input("请输入您要借阅的图书编号：")
amount=int(input("请输入您要借阅的书籍个数："))
sql1 = "SELECT * FROM book WHERE booknum='%s'" % (booknum)
cursor.execute(sql1)
result = cursor.fetchone()
res = book_if_borrow(booknum,amount)
if res:
print("您要借阅的书籍书名：%s 作者：%s 书籍编号：%s 出版社: %s 当前剩余：%d本 借后剩余：%d本" %(result[0],result[1],result[2],result[3],result[4],result[4]-amount))
book_borrow_after(amount,booknum)
#db.commit()
borrow_add(name,booknum,amount)
info=select_after_borrow(booknum,name)
print("以下是您的借阅图书信息，注意借阅号，这将是您还书的凭证！\n\
借阅号：%d 借阅人：%s 借阅图书：%s 图书编号：%s 借阅数量：%d 借阅日期：%s 归还日期：%s" %(info[-1][0],info[-1][1],info[-1][2],info[-1][3],info[-1][4],info[-1][5],info[-1][6]))
print("借阅成功")
while True:
a=int(input("请输入您选择:[1]继续借阅 [2]退出"))
if a == 1:
book_borrow(name)
break
elif a == 2 :
break
else:
print("无效操作")
else:
print("借阅失败")
while True:
a=int(input("请输入您选择:[1]继续借阅 [2]退出"))
if a == 1:
book_borrow(name)
break
elif a == 2 :
break
else:
print("无效操作")
db.close()
def back_if_over(id):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "SELECT * FROM borrow WHERE backdate >= CURDATE() AND id = %s" %(id)
cursor.execute(sql)
res=cursor.fetchall()
if res:
return True
else:
return False
db.close()
def book_back_update(id):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "UPDATE book SET bookamount=bookamount+(SELECT borrowamount FROM borrow WHERE id = %s) WHERE booknum=(SELECT bookid FROM borrow WHERE id = %s)" %(id,id)
cursor.execute(sql)
db.commit()
db.close()
def borrow_back_update(id):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "DELETE FROM borrow WHERE id=%s" %(id)
cursor.execute(sql)
db.commit()
db.close()
def book_back():
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
while True:
id = int(input("请输入您的借阅号："))
sql1 = "SELECT * FROM borrow WHERE id=%s" %(id)
cursor.execute(sql1)
info =cursor.fetchone()
if info:
print("以下是您的借阅图书信息，注意借阅号，这将是您还书的凭证！\n\
借阅号：%d 借阅人：%s 借阅图书：%s 图书编号：%s 借阅数量：%d 借阅日期：%s 归还日期：%s" % (info[0], info[1], info[2], info[3], info[4], info[5], info[6]))
choice=int(input("请确认您的归还借书信息：[1]确认 [2]返回 [3]退出"))
if choice == 1 :
#判断是否逾期：
if back_if_over(id):
book_back_update(id)
borrow_back_update(id)
print("还书成功")
break
else:
print("您已逾期，请联系管理员！")
break
elif choice == 2:
continue
elif choice == 3 :
break
else:
print("无效输入")
else:
print("请输入正确的借阅号")
def borrow_info_again(id,day):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql1 = "SELECT * FROM borrow WHERE id=%s" % (id)
cursor.execute(sql1)
info = cursor.fetchone()
print("以下是您的借阅图书信息:\n\
借阅号：%d 借阅人：%s 续借天数：%d 借阅图书：%s 图书编号：%s 借阅数量：%d 初始借阅日期：%s 归还日期：%s" %(info[0], info[1],day,info[2], info[3], info[4], info[5], info[6]))
db.close()
def borrow_update_again(id):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
a=int(input("请输入您的续借天数（不超过31天）:"))
if a > 31 :
print("您的借阅天数已超过系统权限，如要借阅，请联系管理员！")
else:
sql="UPDATE borrow SET backdate=DATE_ADD(backdate,INTERVAL %s DAY) WHERE id=%s" %(a,id)
cursor.execute(sql)
db.commit()
db.close()
return a
def borrow_again():
id=int(input("输入您的借阅号："))
if back_if_over(id):
day=borrow_update_again(id)
borrow_info_again(id,day)
print("续借成功")
else:
print("您已逾期，请先联系管理员再进行操作，谢谢！")
def borrow_info_select(name):
db = pymysql.connect("localhost", "ljz", "redhat", "bbs")
cursor = db.cursor()
sql = "SELECT * FROM borrow WHERE borrowname='%s'" %(name)
cursor.execute(sql)
res=cursor.fetchall()
if res:
for i in range(len(res)):
print("以下是您的第%d条借阅图书信息:\n\
借阅号：%d 借阅人：%s 借阅图书：%s 图书编号：%s 借阅数量：%d 借阅日期：%s 归还日期：%s" % (i+1,res[i][0], res[i][1], res[i][2], res[i][3], res[i][4], res[i][5], res[i][6]))
else:
print("您没有借阅图书")
db.close()最后小编想说的是我在这里没有加入图形化或者web，如果有人有兴趣继续做下去的话可以添加自己喜欢的东西，希望对大家有帮助。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
