Django学习记录3-连接数据库

1.在项目目录下settings.py配置连接的数据库信息

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'student',         # 你要存储数据的库名，事先要创建。
        'USER': 'root',         # 数据库用户名
        'PASSWORD': 'root',     # 密码
        'HOST': 'localhost',    # 默认主机
        'PORT': '3306',         # 数据库使用的端口
    }
}

2.在应用目录下models.py 创建一个表信息操作的Model表

from django.db import models

# Create your models here.
class Stu(models.Model):
    id = models.AutoField(primary_key=True)
    name = models.CharField(max_length=16)
    age = models.SmallIntegerField()
    sex = models.CharField(max_length=1)
    classid = models.CharField(max_length=8)

    def __str__(self) :
        return "%d:%s:%d:%s:%s"%(self.id, self.name, self.age, self.sex, self.classid)
    
    class Meta:
        db_table = "stu"

3.激活模型

在项目目录下settings.py添加应用程序

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    "my_app" #添加应用
]

4.调用

(1).进入交互式的Python shell 

C:\Users\78461\Desktop\mysite>python manage.py shell
Python 3.9.4 (tags/v3.9.4:1f2e308, Apr  6 2021, 13:40:21) [MSC v.1928 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from my_app.models import Stu
>>> mod = Stu.objects
>>> lists = mod.all()
>>> for u in lists:
...     print(u)
...
1:张三:18:male:python1
2:李四:17:male:python2
3:王五:18:female:python1
4:陆六:19:female:python2
>>> mod.get(id = 1)
<Stu: 1:张三:18:male:python1>

(2).在my_app应用的视图中

在应用目录下，views.py文件

from django.shortcuts import render
from django.views.decorators.csrf import csrf_exempt
# Create your views here.

from django.http import HttpResponse
from my_app.models import Stu

def index(request):
    lists = Stu.objects.all()
    print(lists)
    print(Stu.objects.get(id = 1))
    return HttpResponse("ok")

在应用目录下，添加路由地址

from django.urls import path
from . import views

urlpatterns = [
    path("",views.index, name="Student")
]

在项目目录下，添加路由地址

from django.contrib import admin
from django.urls import path
from django.conf.urls import include, url
from my_app import views


urlpatterns = [
    #path('admin/', admin.site.urls),
    url("stu/", include("my_app.urls"))
]

在项目目录路径下运行cmd

python manage.py runserver