【2020Python修炼记】web框架之choices 参数/MTV 与 MVC 模型/多对多关系的创建方法
【目录】
一、choices 参数
二、MTV 与 MVC 模型
三、多对多关系的三种创建方法
一、choices 参数
""" 用户表 性别 学历 工作经验 是否结婚 是否生子 客户来源 ... 针对某个可以列举完全的可能性字段,我们应该如何存储? 只要某个字段的可能性是可以列举完全的,那么一般情况下都会采用choices参数 """
class User(models.Model): username = models.CharField(max_length=32) age = models.IntegerField() # 性别 gender_choices = ( (1,'男'), (2,'女'), (3,'其他'), ) gender = models.IntegerField(choices=gender_choices) score_choices = ( ('A','优秀'), ('B','良好'), ('C','及格'), ('D','不合格'), ) # 保证字段类型跟列举出来的元祖第一个数据类型一致即可 score = models.CharField(choices=score_choices,null=True) """ 该gender字段存的还是数字 但是如果存的数字在上面元祖列举的范围之内 那么可以非常轻松的获取到数字对应的真正的内容 1.gender字段存的数字不在上述元祖列举的范围内容 2.如果在 如何获取对应的中文信息 """ from app01 import models # models.User.objects.create(username='jason',age=18,gender=1) # models.User.objects.create(username='egon',age=85,gender=2) # models.User.objects.create(username='tank',age=40,gender=3) # 存的时候 没有列举出来的数字也能存(范围还是按照字段类型决定) # models.User.objects.create(username='tony',age=45,gender=4) # 取 # user_obj = models.User.objects.filter(pk=1).first() # print(user_obj.gender) # 只要是choices参数的字段 如果你想要获取对应信息 固定写法 get_字段名_display() # print(user_obj.get_gender_display()) user_obj = models.User.objects.filter(pk=4).first() # 如果没有对应关系 那么字段是什么还是展示什么 print(user_obj.get_gender_display()) # 4
# 实际项目案例 # CRM相关内部表 class School(models.Model): """ 校区表 如: 北京沙河校区 上海校区 """ title = models.CharField(verbose_name='校区名称', max_length=32) def __str__(self): return self.title class Course(models.Model): """ 课程表 如: Linux基础 Linux架构师 Python自动化开发精英班 Python自动化开发架构师班 Python基础班 go基础班 """ name = models.CharField(verbose_name='课程名称', max_length=32) def __str__(self): return self.name class Department(models.Model): """ 部门表 市场部 1000 销售 1001 """ title = models.CharField(verbose_name='部门名称', max_length=16) code = models.IntegerField(verbose_name='部门编号', unique=True, null=False) def __str__(self): return self.title class UserInfo(models.Model): """ 员工表 """ name = models.CharField(verbose_name='员工姓名', max_length=16) email = models.EmailField(verbose_name='邮箱', max_length=64) depart = models.ForeignKey(verbose_name='部门', to="Department",to_field="code") user=models.OneToOneField("User",default=1) def __str__(self): return self.name class ClassList(models.Model): """ 班级表 如: Python全栈 面授班 5期 10000 2017-11-11 2018-5-11 """ school = models.ForeignKey(verbose_name='校区', to='School') course = models.ForeignKey(verbose_name='课程名称', to='Course') semester = models.IntegerField(verbose_name="班级(期)") price = models.IntegerField(verbose_name="学费") start_date = models.DateField(verbose_name="开班日期") graduate_date = models.DateField(verbose_name="结业日期", null=True, blank=True) memo = models.CharField(verbose_name='说明', max_length=256, blank=True, null=True, ) teachers = models.ManyToManyField(verbose_name='任课老师', to='UserInfo',limit_choices_to={'depart':1002}) tutor = models.ForeignKey(verbose_name='班主任', to='UserInfo',related_name="class_list",limit_choices_to={'depart':1006}) def __str__(self): return "{0}({1}期)".format(self.course.name, self.semester) class Customer(models.Model): """ 客户表 """ qq = models.CharField(verbose_name='qq', max_length=64, unique=True, help_text='QQ号必须唯一') name = models.CharField(verbose_name='学生姓名', max_length=16) gender_choices = ((1, '男'), (2, '女')) gender = models.SmallIntegerField(verbose_name='性别', choices=gender_choices) education_choices = ( (1, '重点大学'), (2, '普通本科'), (3, '独立院校'), (4, '民办本科'), (5, '大专'), (6, '民办专科'), (7, '高中'), (8, '其他') ) education = models.IntegerField(verbose_name='学历', choices=education_choices, blank=True, null=True, ) graduation_school = models.CharField(verbose_name='毕业学校', max_length=64, blank=True, null=True) major = models.CharField(verbose_name='所学专业', max_length=64, blank=True, null=True) experience_choices = [ (1, '在校生'), (2, '应届毕业'), (3, '半年以内'), (4, '半年至一年'), (5, '一年至三年'), (6, '三年至五年'), (7, '五年以上'), ] experience = models.IntegerField(verbose_name='工作经验', blank=True, null=True, choices=experience_choices) work_status_choices = [ (1, '在职'), (2, '无业') ] work_status = models.IntegerField(verbose_name="职业状态", choices=work_status_choices, default=1, blank=True, null=True) company = models.CharField(verbose_name="目前就职公司", max_length=64, blank=True, null=True) salary = models.CharField(verbose_name="当前薪资", max_length=64, blank=True, null=True) source_choices = [ (1, "qq群"), (2, "内部转介绍"), (3, "官方网站"), (4, "百度推广"), (5, "360推广"), (6, "搜狗推广"), (7, "腾讯课堂"), (8, "广点通"), (9, "高校宣讲"), (10, "渠道代理"), (11, "51cto"), (12, "智汇推"), (13, "网盟"), (14, "DSP"), (15, "SEO"), (16, "其它"), ] source = models.SmallIntegerField('客户来源', choices=source_choices, default=1) referral_from = models.ForeignKey( 'self', blank=True, null=True, verbose_name="转介绍自学员", help_text="若此客户是转介绍自内部学员,请在此处选择内部学员姓名", related_name="internal_referral" ) course = models.ManyToManyField(verbose_name="咨询课程", to="Course") status_choices = [ (1, "已报名"), (2, "未报名") ] status = models.IntegerField( verbose_name="状态", choices=status_choices, default=2, help_text=u"选择客户此时的状态" ) consultant = models.ForeignKey(verbose_name="课程顾问", to='UserInfo', related_name='consultanter',limit_choices_to={'depart':1001}) date = models.DateField(verbose_name="咨询日期", auto_now_add=True) recv_date = models.DateField(verbose_name="当前课程顾问的接单日期", null=True) last_consult_date = models.DateField(verbose_name="最后跟进日期", ) def __str__(self): return self.name class ConsultRecord(models.Model): """ 客户跟进记录 """ customer = models.ForeignKey(verbose_name="所咨询客户", to='Customer') consultant = models.ForeignKey(verbose_name="跟踪人", to='UserInfo',limit_choices_to={'depart':1001}) date = models.DateField(verbose_name="跟进日期", auto_now_add=True) note = models.TextField(verbose_name="跟进内容...") def __str__(self): return self.customer.name + ":" + self.consultant.name class Student(models.Model): """ 学生表(已报名) """ customer = models.OneToOneField(verbose_name='客户信息', to='Customer') class_list = models.ManyToManyField(verbose_name="已报班级", to='ClassList', blank=True) emergency_contract = models.CharField(max_length=32, blank=True, null=True, verbose_name='紧急联系人') company = models.CharField(verbose_name='公司', max_length=128, blank=True, null=True) location = models.CharField(max_length=64, verbose_name='所在区域', blank=True, null=True) position = models.CharField(verbose_name='岗位', max_length=64, blank=True, null=True) salary = models.IntegerField(verbose_name='薪资', blank=True, null=True) welfare = models.CharField(verbose_name='福利', max_length=256, blank=True, null=True) date = models.DateField(verbose_name='入职时间', help_text='格式yyyy-mm-dd', blank=True, null=True) memo = models.CharField(verbose_name='备注', max_length=256, blank=True, null=True) def __str__(self): return self.customer.name class ClassStudyRecord(models.Model): """ 上课记录表 (班级记录) """ class_obj = models.ForeignKey(verbose_name="班级", to="ClassList") day_num = models.IntegerField(verbose_name="节次", help_text=u"此处填写第几节课或第几天课程...,必须为数字") teacher = models.ForeignKey(verbose_name="讲师", to='UserInfo',limit_choices_to={'depart':1002}) date = models.DateField(verbose_name="上课日期", auto_now_add=True) course_title = models.CharField(verbose_name='本节课程标题', max_length=64, blank=True, null=True) course_memo = models.TextField(verbose_name='本节课程内容概要', blank=True, null=True) has_homework = models.BooleanField(default=True, verbose_name="本节有作业") homework_title = models.CharField(verbose_name='本节作业标题', max_length=64, blank=True, null=True) homework_memo = models.TextField(verbose_name='作业描述', max_length=500, blank=True, null=True) exam = models.TextField(verbose_name='踩分点', max_length=300, blank=True, null=True) def __str__(self): return "{0} day{1}".format(self.class_obj, self.day_num) class StudentStudyRecord(models.Model): ''' 学生学习记录 ''' classstudyrecord = models.ForeignKey(verbose_name="第几天课程", to="ClassStudyRecord") student = models.ForeignKey(verbose_name="学员", to='Student') record_choices = (('checked', "已签到"), ('vacate', "请假"), ('late', "迟到"), ('noshow', "缺勤"), ('leave_early', "早退"), ) record = models.CharField("上课纪录", choices=record_choices, default="checked", max_length=64) score_choices = ((100, 'A+'), (90, 'A'), (85, 'B+'), (80, 'B'), (70, 'B-'), (60, 'C+'), (50, 'C'), (40, 'C-'), (0, ' D'), (-1, 'N/A'), (-100, 'COPY'), (-1000, 'FAIL'), ) score = models.IntegerField("本节成绩", choices=score_choices, default=-1) homework_note = models.CharField(verbose_name='作业评语', max_length=255, blank=True, null=True) note = models.CharField(verbose_name="备注", max_length=255, blank=True, null=True) homework = models.FileField(verbose_name='作业文件', blank=True, null=True, default=None) stu_memo = models.TextField(verbose_name='学员备注', blank=True, null=True) date = models.DateTimeField(verbose_name='提交作业日期', auto_now_add=True) def __str__(self): return "{0}-{1}".format(self.classstudyrecord, self.student) """ chocies参数使用场景是非常广泛的 """
二、MTV 与 MVC 模型
# MTV:Django号称是MTV模型
M:models
T:templates
V:views
# MVC:其实django本质也是MVC
M:models
V:views
C:controller
# vue框架:MVVM模型
三、多对多关系的三种创建方法
# 全自动:利用orm自动帮我们创建第三张关系表 class Book(models.Model): name = models.CharField(max_length=32) authors = models.ManyToManyField(to='Author') class Author(models.Model): name = models.CharField(max_length=32) """ 优点:代码不需要你写 非常的方便 还支持orm提供操作第三张关系表的方法... 不足之处:第三张关系表的扩展性极差(没有办法额外添加字段...) """ # 纯手动 class Book(models.Model): name = models.CharField(max_length=32) class Author(models.Model): name = models.CharField(max_length=32) class Book2Author(models.Model): book_id = models.ForeignKey(to='Book') author_id = models.ForeignKey(to='Author') ''' 优点:第三张表完全取决于你自己进行额外的扩展 不足之处:需要写的代码较多,不能够再使用orm提供的简单的方法 不建议你用该方式 ''' # 半自动 class Book(models.Model): name = models.CharField(max_length=32) authors = models.ManyToManyField(to='Author', through='Book2Author', through_fields=('book','author') ) class Author(models.Model): name = models.CharField(max_length=32) # books = models.ManyToManyField(to='Book', # through='Book2Author', # through_fields=('author','book') # ) class Book2Author(models.Model): book = models.ForeignKey(to='Book') author = models.ForeignKey(to='Author') """ through_fields字段先后顺序 判断的本质: 通过第三张表查询对应的表 需要用到哪个字段就把哪个字段放前面 你也可以简化判断 当前表是谁 就把对应的关联字段放前面 半自动:可以使用orm的正反向查询 但是没法使用add,set,remove,clear这四个方法 """ # 总结:你需要掌握的是全自动和半自动 为了扩展性更高 一般我们都会采用半自动(写代码要给自己留一条后路)
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