python对数据库进行增删改查操作
第六单元
案例数据进行增删改查
在settings里配置项目
安装数据库
编写两个模型类
from django.db import models
# Create your models here.
# models.Model 继承
class Department(models.Model):
#
dep_name = models.CharField(max_length=10,verbose_name="部门名称")
desc = models.CharField(max_length=10,verbose_name="部门描述")
class Meta:
verbose_name = '部门表'
verbose_name_plural =verbose_name
db_table = 'depart6'
def __str__(self):
return self.dep_name
class Employee(models.Model):
emp_name = models.CharField(max_length=10,verbose_name="姓名")
job = models.CharField(max_length=10,verbose_name="职业")
salary = models.IntegerField(verbose_name="工资")
# 级联操作
department =models.ForeignKey(to = Department,on_delete=models.CASCADE,verbose_name="部门") #外键
class Meta:
verbose_name = '员工表'
# 复数形式
verbose_name_plural =verbose_name
db_table = 'depar6'
def __str__(self):
return self.emp_name
# 文件迁移，执行迁移文件
# python manage.py makemigrations
# python manage.py migrate
# pythom manage.py createsuperuser
将主表内容展示出来
1、定义主表视图
# 导入部门模型类，和视图
from django.shortcuts import render
from myapp.models import Department
from django.views import View
class zhu(View):
def get(self,request):
date = Department.objects.all()
return render(request,'zhu.html',{'datas':date})
2、子路由路由
from myapp import views
from django.urls import path
urlpatterns = [
path('zhu/',views.zhu.as_view()),
]
3、定义页面进行数据渲染
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
<table border="1px" width="500px">
<tr>
<td>编号td>
<td>名称td>
<td>名称td>
tr>
{% for data in datas %}
<tr>
<td>{{ data.id }}td>
<td>
{{ data.dep_name }}
td>
<td>{{ data.desc }}td>
tr>
{% endfor %}
table>
body>
html>
点击部门会跳转到对应的员工信息表
1、定义员工视图
class yuan(View):
# 这里的id就是html页面传入路由的id
def get(self,request,id):
# 过滤出部门id和传入的id相同的数据
data = Employee.objects.filter(department_id = id).order_by('salary')
return render(request,'yuan.html',{'datas':data})
2、路由
from myapp import views
from django.urls import path
urlpatterns = [
#动态路由根据部门的id查询对应的员工
path('yuan//' ,views.yuan.as_view()),
]
3、点击进行跳转
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
<table border="1px" width="500px">
<tr>
<td>编号td>
<td>名称td>
<td>名称td>
tr>
{% for data in datas %}
<tr>
<td>{{ data.id }}td>
<td>
{# 点击部门名，会由href跳转到对应的路由上，并传递过去id 以post方法进行传递#}
<a href="/yuan/{{ data.id }}/" methods="post">
{{ data.dep_name }}
a>
td>
<td>{{ data.desc }}td>
tr>
{% endfor %}
table>
body>
html>
4、员工的页面
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
<table border="1px" width="500px">
<tr>
<td>编号td>
<td>姓名td>
<td>职业td>
<td>工资td>
<td>部门td>
tr>
{% for data in datas %}
<tr>
<td>{{ data.id }}td>
<td>{{ data.emp_name }}td>
<td>{{ data.job }}td>
<td>{{ data.salary }}td>
<td>{{ data.department }}td>
tr>
{% endfor %}
table>
body>
html>
增加数据
1、定义添加视图
class add(View):
def post(self,request):
# 获取添加的数据
name = request.POST.get('emp_name')
job = request.POST.get('job')
salary = request.POST.get('salary')
department = request.POST.get('department')
try:
Employee.objects.create(
emp_name = name,
job = job,
salary = salary,
department_id = department #外键使用的id
)
except Exception as e:
print(e)
return HttpResponse("添加失败")
return redirect('/zhu/')
2、在员工表下进行添加数据
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
<form action="/add/" method="post">
名字：<input type="text" name="emp_name"><br>
职业<input type="text" name="job"><br>
工资<input type="text" name="salary"><br>
部门<input type="text" name="department"><br>
<input type="submit" value="添加">
form>
body>
html>
3、配置路由
from myapp import views
from django.urls import path
urlpatterns = [
path('add/',views.add.as_view()),
]
删除数据
1、定义视图
class delview(View):
def get(self,request,id):
# 第一种方法 用get也可以
# Employee.objects.filter(id=id).delete()
# return redirect('/zhu/')
# 第二种方法
data = Employee.objects.get(id=id)
dep_id = data.department_id
data.delete()
return redirect(f'/yuan/{dep_id}/')
2、在员工页面添加删除按钮
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
<table border="1px" width="500px">
<tr>
<td>编号td>
<td>姓名td>
<td>职业td>
<td>工资td>
<td>部门td>
<td>操作td>
tr>
{% for data in datas %}
<tr>
<td>{{ data.id }}td>
<td>{{ data.emp_name }}td>
<td>{{ data.job }}td>
<td>{{ data.salary }}td>
<td>{{ data.department }}td>
<td>
{# 点击a发起get请求 #}
<a href="/del/{{ data.id }}/">删除a>
td>
tr>
{% endfor %}
table>
body>
html>
3、配置路由
from myapp import views
from django.urls import path
urlpatterns = [
# 动态路由
path('del//' ,views.delview.as_view()),
]
修改
1、修改视图
class update(View):
# 路由传递过来的id
def get(self,request,id):
data = Employee.objects.get(id=id)
# get获取单个数据
# 将id相同的数据传递到udp页面
return render(request,'upd.html',{'datas':data})
def post(self,request,id):
# 获取uod里面的数据
name = request.POST.get('name')
job = request.POST.get('job')
salary = request.POST.get('salary')
department = request.POST.get("department")
try:
# 只有filter 有update的功能
Employee.objects.filter(id=id).update(
emp_name=name,
job =job,
salary =salary,
department_id =department
)
except Exception as e:
print(e)
return HttpResponse("修改失败")
return redirect('/zhu/')
2、路由
from myapp import views
from django.urls import path
urlpatterns = [
# 动态路由传入id 要修改员工的id
path('upd//' ,views.update.as_view()),
]
3、点击修改，跳转到修改页面
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
<table border="1px" width="500px">
<tr>
<td>编号td>
<td>姓名td>
<td>职业td>
<td>工资td>
<td>部门td>
<td>操作td>
tr>
{% for data in datas %}
<tr>
<td>{{ data.id }}td>
<td>{{ data.emp_name }}td>
<td>{{ data.job }}td>
<td>{{ data.salary }}td>
<td>{{ data.department }}td>
<td>
{# 点击a发起get请求 #}
<a href="/upd/{{ data.id }}/">修改a>
td>
tr>
{% endfor %}
table>
body>
html>
4、修改页面
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
{# 不用action默认传递到本视图 #}
<form method="post">
{# value将数据绑定#}
名字：<input type="text" value="{{ datas.emp_name }}" name="name"><br>
工作：<input type="text" value="{{ datas.job }}" name="job"><br>
工资：<input type="text" value="{{ datas.salary }}" name="salary"><br>
部门：<input type="text" value="{{ datas.department_id }}" name="department"><br>
<input type="submit" value="修改">
form>
body>
html>
查询员工
1、查询视图
class search(View):
def get(self,request):
name = request.GET.get('name')
try:
data = Employee.objects.get(emp_name__contains=name)
except Exception as e:
print(e)
return HttpResponse("查询失败")
# 直接返回查询的内容
return HttpResponse(f'{data.emp_name},{data.job},{data.salary},{data.department}')
2、路由
from myapp import views
from django.urls import path
urlpatterns = [
path('search/',views.search.as_view())
]
3、查询的页面
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<form action="/search/" method="get">
名字：<input type="text" name="name">
<input type="submit" value="搜索">
form>
body>
html>