Django Model

django的模型挺好的，不用自己写SQL。外键，多对多，一对多，多对一。

# app_1/models.py
# -*- coding: utf-8 -*-


from __future__ import unicode_literals

from django.db import models

from app_2.models import App2Model1, App2Model2

class App1Model1(models.Model):
    field_1 = models.IntegerField()
    field_2 = models.IntegerField()
    field_3 = models.IntegerField()
    field_4 = models.ForeignKey(App2Model1)
    field_5 = models.ForeignKey(App2Model2)
    field_6 = models.ForeignKey("App1Model2", on_delete=models.CASCADE)

class App1Model2(models.Model):
    field_1  = models.CharField(max_length=500)
    field_2  = models.CharField(max_length=1)
    field_3 = models.ForeignKey(App2Model1)
    field_4  = models.CharField(max_length=500)

参考：
Django Project