单表的增删改查
----- 增加2种方式
方法一:
models.Teacher.objects.create(tname="李老师")
方法二:
obj = models.Teacher(tname="王老师")
obj.save()
----- 查询
1、获取所有的值
obj = models.Teacher.objects.all()
print(obj)
<QuerySet [<Teacher: 张老师>, <Teacher: 张老师>, <Teacher: 李老师>, <Teacher: 王老师>]>
2、获取第一个值
obj = models.Teacher.objects.first()
print(obj)
张老师
3、获取最后一值
obj = models.Teacher.objects.last()
print(obj)
王老师
4、查询任意一个
obj = models.Teacher.objects.filter(id=3)
print(obj)
<QuerySet [<Teacher: 李老师>]>
5、查询id大于2的老师
obj = models.Teacher.objects.filter(id__gt=2)
print(obj)
<QuerySet [<Teacher: 李老师>, <Teacher: 王老师>]>
6、查询id大于2的第一个老师
obj = models.Teacher.objects.filter(id__gt=2).first()
print(obj)
李老师
----- 修改
models.Teacher.objects.filter(id=3).update(tname="wangsi")
----- 删除
models.Teacher.objects.filter(id=3).delete()
view.py
from django.shortcuts import render,HttpResponse,redirect from ormapp import models def index(request): #增加2种方法 # models.Teacher.objects.create(tname="李老师") # obj = models.Teacher(tname="王老师") # obj.save() #查询 # obj = models.Teacher.objects.all() 获取所有 # obj = models.Teacher.objects.first() 获取第一个 # obj = models.Teacher.objects.last() 获取最后一个 # obj = models.Teacher.objects.filter(id=3) 查询任意一个 # obj = models.Teacher.objects.filter(id__gt=2) 查询id大于2的老师 # obj = models.Teacher.objects.filter(id__gt=2).first() 查询id大于2的第一个老师 models.Teacher.objects.filter(id=3).update(tname="wangsi") models.Teacher.objects.filter(id=3).delete() return HttpResponse("填加成功")
models.py
from django.db import models class Teacher(models.Model): tname = models.CharField(max_length=32) def __str__(self): return self.tname class Classes(models.Model): title = models.CharField(max_length=32) ct = models.ManyToManyField("Teacher") def __str__(self): return self.name class student(models.Model): name = models.CharField(max_length=32) age = models.BooleanField(default='男') sc = models.ForeignKey(Classes,on_delete=True) """定义每个数据对象的显示信息""" def __str__(self): return self.name
urls.py
""" from django.contrib import admin from django.urls import path from ormapp import views urlpatterns = [ path('index/', views.index), ]