配置
一： 新建app
python manage.py startapp books
二：setting.py添加app
INSTALLED_APPS = (
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'books', #添加的app
)
三：连接mysql配置
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'mysite',
'USER': 'root',
'PASSWORD': '123456',
'HOST': 'localhost',
'PORT': '3306',
}
}
四：编辑models
from django.db import models
#出版社信息表
class Publisher(models.Model):
name = models.CharField(max_length=20)
address = models.CharField(max_length=50)
city = models.CharField(max_length=60)
state_province = models.CharField(max_length=30)
country = models.CharField(max_length=50)
website = models.URLField()
def __unicode__(self):
return self.name
#作者表
class Auther(models.Model):
first_name = models.CharField(max_length=30)
last_name = models.CharField(max_length=30)
email = models.EmailField()
def __unicode__(self):
return"%s %s"%(self.first_name,self.last_name)
#书籍表
class Books(models.Model):
title = models.CharField(max_length=100)
authors = models.ManyToManyField(Auther)
publisher = models.ForeignKey(Publisher)
publication_date = models.DateField()
def __unicode__(self):
return self.title
解释：
_unicode方法:用来以字符串来显示查询的时候所查询到的数据，如果不加则全显示为object无法知道是哪一条数据，Python版本为3.*使用_str
五：将表结构写入数据库
python manage.py makemigrations
python manage.py migrate
使用
进入django shell命令行
python manage.py shell
>>> from books.models import *
- 增：
p1 = Publisher.objects.create(name='Apress', address='2855 Telegraph Avenue',city='Berkeley', state_province='CA', country='U.S.A.',website='http://www.apress.com/')
p2 = ....
- 查(查询多个)：
1.查询所有
Publisher.objects.all()
2.过滤查询
#select xxx,xxx from Publisher where city="Berkeley"
Publisher.objects.filter(city="Berkeley")
#select xxx,xxx from Publisher where city="Berkeley" and name="Apress"
Publisher.objects.filter(city="Berkeley",name="Apress")
python =是精确匹配，要实现like语句则使用__contains
#select xxx,xxx from Publisher where name like "%press%"
Publisher.objects.filter(name__contains="press")
3.排序查询
正向排序
Publisher.objects.order_by("name")
#或
Publisher.objects.order_by("name"，"city")
#第二个参数会在第一个相同的情况下被使用
逆向排序(参数前面加一个减号即可)
Publisher.objects.order_by("-name")
4.查询指定字段
values:
Publisher.objects.values("name")
#返回列表内嵌字典
[{"name":"Apress"},{"name":"..."},....]
values_list:
Publisher.objects.values_list("name")
#返回列表内嵌元祖
[("Apress"),("..."),...]
- 查(查询单个)
Publisher.objects.get(name="Apress")
注：如果获取单个为空会触发DoesNotExist 异常，需要用try处理：
try:
p = Publisher.objects.get(name='Apress')
except Publisher.DoesNotExist:
print "Apress isn't in the database yet."
else:
print "Apress is in the database."
- 改
改一个
Publisher.objects.filter(id=1).update(name='Apress Publishing')
改多个
Publisher.objects.all().update(country='USA')
注：django修改数据，先查询要改的数据，然后update
- 删
Publisher.objects.filter(country='USA').delete()
注：删除数据和更新数据一样，先查询后delete
