python Django连接MySQL数据库做增删改查
1、下载安装MySQLdb类库
http://www.djangoproject.com/r/python-mysql/
2、修改settings.py 配置数据属性
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.
'NAME': 'djangodb', # Or path to database file if using sqlite3.
# The following settings are not used with sqlite3:
'USER': 'root',
'PASSWORD': 'root',
'HOST': '127.0.0.1', # Empty for localhost through domain sockets or '127.0.0.1' for localhost through TCP.
'PORT': '3306', # Set to empty string for default.
}
}
修改完后进入DOS进入项目目录下执行python manage.py shell命令启动交互界面输入一下代码验证数据库配置是否成功。没报错则成功!
>>> from django.db import connection
>>> cursor = connection.cursor()
3、创建一个Django app
一个项目中包含一个或多个这样的app。app可以理解为一块功能集合。比如产品管理模块就包含增删该查等功能,可以把产品管理叫做一个app。每个Django app都有独立的models,views等,易移植和被复用。
DOS进入项目目录 执行 python manage.py startapp products生成目录文件如下:
products/
__init__.py
models.py
tests.py
views.py
4、编写models
from django.db import models
# Create your models here.
class Company(models.Model):
full_name = models.CharField(max_length=30)
address = models.CharField(max_length=50)
tel = models.CharField(max_length=15,blank=True)
class Product(models.Model):
product_name = models.CharField(max_length=30)
price = models.FloatField()
stock = models.IntegerField(max_length=5)
company = models.ForeignKey(Company)
5、模型安装(修改settings.py)
INSTALLED_APPS = (
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.sites',
'django.contrib.messages',
'django.contrib.staticfiles',
# Uncomment the next line to enable the admin:
'django.contrib.admin',
# Uncomment the next line to enable admin documentation:
'django.contrib.admindocs',
'DjangoMysqlSite.products',
)
采用 python manage.py validate 检查模型的语法和逻辑是否正确。
没有错误则执行 python manage.py syncdb创建数据表。
现在你可以看到你的数据库除了生成了products_company,products_product外还创建了其它好几个表,这些是django管理后台所需表暂不管。
6、简单的增删改查
进入python manage.py shell
from DjangoMysqlSite.products.models import Company
>>> c = Company(full_name='集团',address='杭州西湖',tel=8889989)
>>> c.save()
>>> company_list = Company.objects.all()
>>> company_list
>>> c = Company.objects.get(full_name="集团")
>>> c.tel = 123456
>>> c.save()
>>> c = Company.objects.get(full_name="集团")
>>> c.delete()
#删除所有
>>> Company.objects.all().delete()

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