Python__员工信息表

作业如下：

#Author wangmengzhu
import os

def select():
    '''
           查询语法如下:
           select name,age from staff_table where age > 22
       　　select  * from staff_table where dept = "IT"
         select  * from staff_table where enroll_date like "2013"
           '''
    data = input('请输入你的命令>>: ')
    data1 = data.split(' ')
    #print(data1)
    if data == ("select name,age from staff_table where age > %s" % (data1[7])):
        with open('作业.txt', 'r+', encoding='utf-8') as f:
            list1 = []
            count = 0
            for line in f:
                i = line.strip().split(',')
                if i[2] > data1[7]:
                    list1.append(i)
            for s in list1:
                count = count + 1
            print('满足条件的个数为>>:%s'%(count))
                #print(list1)
            for j in list1:
                print(j)
    elif data == ('select * from staff_table where dept = %s'%(data1[7])):
        with open('作业.txt', 'r+', encoding='utf-8') as f:
            list2 = []
            count = 0
            for line in f:
                i = line.strip().split(',')
                if i[4] == data1[7]:
                    list2.append(i)
                    for s in list2:
                        count = count + 1
                    print('满足条件的个数为>>:%s' % (count))
                    # print(list1)
                    for j in list2:
                        print(j)
    elif data == ('select * from staff_table where enroll_date like %s'%(data1[7])):
        with open('作业.txt', 'r+', encoding='utf-8') as f:
            list3 = []
            list4 = []
            count = 0
            for line in f:
                i = line.strip().split(',')
                list3.append(i)
                #print(list3)
            for j in list3:
                m = j[5].split('-')
                if m[0] == data1[7]:
                    list4.append(j)
            for s in list4:
                count = count + 1
            print('满足条件的条数为>>:%s'%(count))
            for j in list4:
                print(j)
    else:
        print('你输入的命令不合法！！')
def add():
    '''
    注释信息：
    可创建新员工纪录，以phone做唯一键，staff_id需自增
    name,age,phone,dept,enroll-date
    例如：mengzhu,23,12345678901,IT,2013-04-01
    '''
    data = input('请输入你的命令>>: ')
    data1 = data.split(',')
    with open('作业.txt','r+',encoding = 'utf-8') as f:
        list5 = []
        for line in f:
            s = line.strip().split(',')
            m = s[3]
            list5.append(m)
        if data1[2] in list5:
            print('这条记录已经存在')
            exit()
        else:
            my_index = str(len(list5)+1)
            data1.insert(0,my_index)
            data1 = ','.join(data1)
        f.write('
')
        f.write(data1)
def delete():
    '''
      注释信息：
          可删除指定员工信息纪录，输入员工id，即可删除
          delete * from staff_table where id = 3
      '''
    data = input('请输入你要删除的命令>>: ')
    data1 = data.split(' ')
    with open('作业.txt','r+',encoding = 'utf-8') as f,
        open('new.txt','w+',encoding = 'utf-8') as f1:
        if data == ('delete * from staff_table where id = %s'%(data1[7])):
            for line in f:
                i = line.strip().split(',')
                if i[0] != data1[7]:
                    i = ','.join(i)
                    f1.write(i)
                    f1.write('
')
                else:
                    continue


os.remove('作业.txt')
os.rename('new.txt', '作业.txt')
def update():
    '''
           注释信息：
           可修改员工信息，语法如下:
       　　UPDATE staff_table SET dept="Market" WHERE where dept = "IT"
           '''
    data = input('请输入你要更改的命令>>: ')
    data1 = data.split(' ')
    if data == ('UPDATE staff_table SET dept = %s where dept = %s'%(data1[5],data1[9])):
        with open('作业.txt','r+',encoding = 'utf-8') as f:
            for line in f:
                i = line.strip().split(',')
                #print(i)
                if i[4] == data1[9]:
                    i[4] = data1[5]
                    print(i)
                else:
                    continue

def main():
    cmd_dic = {
        'select':select,
        'delete':delete,
        'update':update,
        'add':add
    }
    while True:
        sql = input('输入要查询的sql语句>>: ').strip()
        if not sql:continue
        cmd_info = sql.split()
        cmd = cmd_info[0]
        if cmd in cmd_dic:
            cmd_dic[cmd]()
        else:
            print('cmd not exists')

main()