Python之创建数据库及功能示例样本

创建数据库实例

import pymysql
db= pymysql.connect(host="localhost",user="root",password="1234",charset="utf8")
cursor=db.cursor()
cursor.execute("create database 数据库名 default charset=utf8;")
db= pymysql.connect(host="localhost",user="root",password="000000",charset="utf8",db="数据库名")
cursor=db.cursor()
cursor.execute('''
create table 表名(
    SNO varchar(20),
    SNAME char(5) ,
    SAGE int(5),
    SSEX char(5),
    SACADEMY char(10),
    SGRADE char(10),
    SCLASS char(5),
    primary key(SNO)
    )default charset=utf8;
''')
cursor.execute('''
insert into 表名 values('2016081111','张三','20','男','软件工程学院','2016','3'),('2016061111','王杰','21','男','网络工程学院','2016','3'),
    ('2016071113','周顺','19','男','大气科学学院','2016','3'),('2017081180','李伟','20','男','软件工程学院','2017','2'),('2016081201','王丽','20','女','软件工程学院','2016','5');
db.commit()
cursor.execute('select * from 表名')
for i in cursor.fetchall():
    print(i)
cursor.close()
db.close()

功能搭建

import pymysql
DB=None
class Student():
    def select(self):
        cursor=DB.cursor()
        try:
            SQL="select * from student"
            cursor.execute(SQL)
            for i in cursor.fetchall():
                print(i)
        except Exception as e:
            print("报错",e)
        finally:
            cursor.close()
    #查询
    def Cha(self):
        try:
            cursor = DB.cursor()
            a=input("请输入学号:")
            cursor.execute("select * from student where SNO=%s"%a)
            if cursor.fetchall():
                SQL = "select * from student where SNO=%s"%a
                cursor.execute(SQL)
                for i in cursor.fetchall():
                    print(i)
            else:
                print("\n查询失败\n")
        except Exception as e:
            print("报错",e)
        finally:
            cursor.close()
    #添加
    def add(self):
        cursor = DB.cursor()
        a = input("输入添加的学号:")
        b = input("输入添加的姓名:")
        c = input("输入添加的年龄:")
        d = input("输入添加的性别:")
        e = input("输入添加的院系:")
        f = input("输入添加的年级:")
        g = input("输入添加的班级:")
        try:
            SQL = "insert into student values ('%s','%s','%s','%s','%s','%s','%s');" % (a, b, c, d, e, f, g)
            cursor.execute(SQL)
            DB.commit()
            print("\n添加成功\n")
        except Exception as e:
            print("报错",e)
        finally:
            cursor.close()
     #修改
    def modify(self):
        cursor = DB.cursor()
        a = input("输入您要修改的学号:")
        b = input("姓名修改为:")
        c = input("年龄修改为:")
        d = input("性别修改为:")
        e = input("学院修改为:")
        f = input("年级修改为:")
        g = input("班级修改为:")
        try:
            SQL = "update student set SNAME='%s',SAGE='%s',SSEX='%s',SACADEMY='%s',SGRADE='%s',SCLASS='%s' where SNO='%s';" % (b,c,d,e,f,g,a)
            cursor.execute(SQL)
            DB.commit()
            print("\n修改成功\n")
            for i in cursor.fetchall():
                print(i)
        except Exception as e:
            print("报错",e)
        finally:
            cursor.close()
     #删除
    def drop(self):
        try:
            cursor = DB.cursor()
            a=input("输入您要删除的学生学号:")
            cursor.execute("select * from student where SNO=%s"%a)
            if cursor.fetchall():
                SQL="delete from student where SNO=%s" % a
                cursor.execute(SQL)
                DB.commit()
                print("\n删除成功\n")
                for i in cursor.fetchall():
                    print(i)
            else:
                print("\n删除失败,可能没有该学号\n")
        except Exception as e:
            print("报错",e)
        finally:
            cursor.close()

def main():
    global DB
    student=Student()
    DB=pymysql.connect(host="localhost",user="root",password="1234",charset="utf8",db="zzz")
    choose=input("请选择您的操作\n"
          "1.查询所有学生的信息\n"
          "2.按学号查询学生的信息\n"
          "3.添加学生信息\n"
          "4.修改学生信息\n"
          "5.删除学生信息\n"
          "6.退出\n")
    while choose != "6":
        if choose == "1":
            student.select()

        elif choose == "2":
            student.Cha()

        if choose == "3":
            student.add()

        if choose == "4":
            student.modify()

        if choose == "5":
            student.drop()

        choose = input("请选择您的操作\n"
                      "1.查询所有学生的信息\n"
                      "2.按学号查询学生的信息\n"
                      "3.添加学生信息\n"
                      "4.修改学生信息\n"
                      "5.删除学生信息\n"
                      "6.退出\n")
    else:
        print("\n您已退出学生信息表\n")

main()