django使用记录

安装virtualenv

easy_install virtualenv

生成虚拟环境

virtualenv myenv

进入虚拟环境

cd myenv

. bin/activate

 

下载安装django

easy_install django

生成project

django-admin.py startproject mysite

 

运行开发服务器

cd mysite

远程访问

python manage.py runserver 0.0.0.0:8000

浏览器访问：http://xxx.xxx.xxx.xxx:8000

本地访问

python manage.py runserver

浏览器访问http://127.0.0.1:8000/

 

在settings.py中设置数据库信息，

修改DATABASES中的参数

同步表结构信息

python manage.py syncdb

注：需要先安装MySQLdb，不然会出错

生成app，（多个app可组成一个project）

python manage.py startapp myapp

在setttings.py中添加myapp

生成myapp中models中定义的表结构

python manage.py sql myapp

python manage.py syncdb

进入shell模式检视models

python manage.py shell

 

离开虚拟环境

deactivate

 

 

modle 特点

Forward access to one-to-many relationships is cached the first time the related object is accessed. Subsequent accesses to the foreign key on the same object instance are cached. Example:

>>> e = Entry.objects.get(id=2)

>>> print e.blog # Hits the database to retrieve the associated Blog.

>>> print e.blog # Doesn't hit the database; uses cached version.

 

Aggregation

主要是为了实现group by的效果

http://fcamel-life.blogspot.com/2010/04/django-group-by.html