Django(26)创建多表模型

from django.db import models


# Create your models here.


class Clas(models.Model):
    name = models.CharField(max_length=32, unique=True, verbose_name="班级名称")

    class Meta:
        db_table = "db_class"


class Course(models.Model):
    name = models.CharField(max_length=32, unique=True, verbose_name="课程名称")

    class Meta:
        db_table = "db_course"


class Student(models.Model):
    sex_choices = (
        (0, "女"),
        (1, "男"),
        (2, "保密"),
    )

    name = models.CharField(max_length=32, unique=True, verbose_name="姓名")
    age = models.SmallIntegerField(verbose_name="年龄", default=18)  # 年龄
    sex = models.SmallIntegerField(choices=sex_choices)
    birthday = models.DateField()

    # 一对多
    # on_delete= 关联关系的设置
    # models.CASCADE    删除主键以后, 对应的外键所在数据也被删除
    # models.DO_NOTHING 删除主键以后, 对应的外键不做任何修改
    # 反向查找字段 related_name
    clas = models.ForeignKey("Clas", on_delete=models.CASCADE)

    # 多对多
    # 建立多对多的关系,ManyToManyField可以建在两个模型中的任意一个，自动创建第三张表
    courses = models.ManyToManyField("Course", db_table="db_student2course")

    # 一对一,使用同一对多
    stu_detail = models.OneToOneField("StudentDetail", on_delete=models.CASCADE)

    class Meta:
        db_table = "db_student"

    def __str__(self):
        return self.name


class StudentDetail(models.Model):
    tel = models.CharField(max_length=32)
    email = models.EmailField()
    description = models.TextField(null=True, verbose_name="个性签名")

    class Meta:
        db_table = "db_student_detail"