Django学习- ORM基础操作

Django学习- ORM基础操作_创建数据

ORM操作：

管理器对象：

创建数据：

Django shell

想要操作模型对象，首先我们需要把它引进Django shell中

>>> from bookstore.models import Book
>>> b1 = Book.objects.create(title='AI', pub='清华大学出版社', price= 20,market_price = 25)
>>> b2 = Book(title='爱',pub='清华大学出版社',price=70,market_price = 50)
>>> b2.save()

查询数据：

例子：

第一步：在django学习下的settings中添加bookstore

INSTALLED_APPS = ['django.contrib.admin','django.contrib.auth','django.contrib.contenttypes','django.contrib.sessions','django.contrib.messages','django.contrib.staticfiles',# 'music',# 'news',# 'sport','bookstore'
]

第二步：在 django学习下的urls添加bookstore

from django.contrib import admin
from django.urls import path,include,re_path
from . import viewsurlpatterns = [path('admin/', admin.site.urls),# 主路由链接需要加/#path('music/',include("music.urls")),#path('sport/',include("sport.urls")),#path('news/',include("news.urls")),path('bookstore/',include('bookstore.urls'))
]

第三步：在bookstore的模型和视图以及url

urls.py:

from django.urls import path
from . import viewsurlpatterns = [path('all_book', views.all_books, name='all_book')
]

views.py:

from django.shortcuts import renderfrom bookstore.models import Book# Create your views here.def all_books(request):books = Book.objects.all()return render(request, 'bookstore/all_book.html',locals())

all_book.html

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>查看所有书籍</title>
</head>
<body>
<table ><tr><th>id</th><th>title</th><th>pub</th><th>price</th><th>market_price</th><th>op</th></tr>{% for book in books %}<tr><td>{{ book.id }}</td><td>{{ book.title }}</td><td>{{ book.pub }}</td><td>{{ book.price }}</td><td>{{ book.market_price }}</td><td><a href="">删除</a><a href="">更新</a></td></tr>{% endfor %}
</table>
</body>
</html>

条件查询：