向同一个模型的外键反向关联名称产生了冲突 一个模型中有两个外键指向同一张表时,创建迁移模型时报错:" HINT: Add or change a related_name argument to the definition for 'AnswersModel.author' or 'AnswersModel.relay_to'."解决方案 class AnswersModel(models.Model): author = models.ForeignKey(FrontUserMod
下面定义两个模型,一个主表,一个字表. 举例说明: 如何通过主表对象找到对应的子表对象? 如何通过子表对象找到对应的主表对象? class Person(models.Model); name = models.CharField('作者姓名', max_length=10) age = models.IntegerField('作者年龄') class Book(models.Model): person = models.ForeignKey(Person,related_name='per
data sqlite> select * from author; id name age 1 jim 12 2 tom 11 sqlite> select * from book; id name author_id 1 learn java 1 2 learn python 1 3 learn c++ 2 models.py # -*- coding: UTF-8 -*- from __future__ import unicode_literals from django.db imp
Django的外键使用 from django.db import models # Create your models here. class Category(models.Model): name = models.CharField(max_length=) class Article(models.Model): title = models.CharField(max_length=) content = models.TextField() # 是由Category影响Artic
# -*- coding: utf-8 -*- """ Tencent is pleased to support the open source community by making 蓝鲸智云(BlueKing) available. Copyright (C) 2017 THL A29 Limited, a Tencent company. All rights reserved. Licensed under the MIT License (the "Li
1.查找表的所有索引(包括索引名,类型,构成列): select t.*,i.index_type from user_ind_columns t,user_indexes i where t.index_name = i.index_name and t.table_name = i.table_name and t.table_name = 要查询的表 2.查找表的主键(包括名称,构成列): select cu.* from user_cons_columns cu, user_constr