【Django】一对多表结构

 1.创建project数据库表

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'app01',       #新增app
]
配置settings.py
from django.db import models

# Create your models here.

class Business(models.Model):
    # id    系统默认id列，自增，主键
    caption = models.CharField(max_length=32)  # 32表示字符长度


class Host(models.Model):
    nid = models.AutoField(primary_key=True)
    hostname = models.CharField(max_length=64,db_index=True)
    ip = models.GenericIPAddressField(protocol='ipv4',db_index=True)
    port = models.IntegerField()
    b = models.ForeignKey(to='Business',to_field='id')
app01/models.py 创建两个简单的数据库表，通过ForeignKey外键关联
运行：
python manage.py makemigrations
python manage.py migrate

 Ok后，使用Navicat Premium软件方可查看！

2.操作数据库表

运行Navicat

点击连接，使用SQLite抓取数据

 点击确认

 获取单表单数据的三种方式

from django.contrib import admin
from django.conf.urls import url
from app01 import views

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^business/', views.business),
]
project/urls
from django.shortcuts import render,HttpResponse,redirect
from app01 import models
# Create your views here.

def business(requset):
    v1 = models.Business.objects.all()
    #QuerySet
    #[obj(id,caption,code),obj(id,caption,code),obj(id,caption,code)]

    v2 = models.Business.objects.all().values('id','caption')
    # QuerySet
    # [{'id':1,'caption':'苹果'},{'id':2,'caption':''香蕉}，{'id':3,'caption':'菠萝'}，{'id':4,'caption':'梨子'}]

    v3 = models.Business.objects.all().values_list('id','caption')
    # QuerySet
    # [(0,苹果)，(2,香蕉)]
    return render(requset,'business.html',{'v1':v1,'v2':v2,'v3':v3})
app01/views.py
from django.db import models

# Create your models here.

class Business(models.Model):
    # id
    caption = models.CharField(max_length=32)
    code = models.CharField(max_length=32,null=True,default='apple')
app01/models.py
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <h1>业务线列表（列表）</h1>
    <ul>
        {% for row in v1 %}
            <li>{{ row.id }}-{{ row.caption }}-{{ row.code }}</li>
        {% endfor %}
    </ul>
    <h1>业务线列表（字典）</h1>
    <ul>
        {% for row in v2 %}
            <li>{{ row.id }}-{{ row.caption }}</li>
        {% endfor %}
    </ul>
    <h1>业务线列表（元组）</h1>
    <ul>
        {% for row in v3 %}
            <li>{{ row.0 }}-{{ row.1 }}</li>
        {% endfor %}
    </ul>
</body>
</html>
templates/business.html

效果图

一对多跨表操作（第一种）

from django.contrib import admin
from django.conf.urls import url
from app01 import views
# from django.urls import path

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^business/', views.business),
    url(r'^host/', views.host),  #在business基础上
]
project/urls.py
from django.db import models

# Create your models here.

class Business(models.Model):
    # id
    caption = models.CharField(max_length=32)
    code = models.CharField(max_length=32,null=True,default='apple')


class Host(models.Model):
    nid = models.AutoField(primary_key=True)
    hostname = models.CharField(max_length=64,db_index=True)
    ip = models.GenericIPAddressField(protocol='ipv4',db_index=True)
    port = models.IntegerField()
    b = models.ForeignKey(to='Business',to_field='id')
app01/models.py
from django.shortcuts import render,HttpResponse,redirect
from app01 import models
# Create your views here.

def host(request):
    v1 = models.Host.objects.filter(nid__gt=0)
    #for row in v1:
        #print(row.nid,row.hostname,row.ip,row.port,row.b_id,row.b.id,row.b.caption,row.b.code,sep='	')

    # return HttpResponse('戴利祥')
    return render(request,'host.html',{'v1': v1})
app01/views.py
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <h1>业务线列表（列表）</h1>
    <table border="1">
        <thead>
            <tr>
                <th>主机名字</th>
                <th>IP</th>
                <th>端口</th>
                <th>业务线名称</th>
                <th>业务线编码</th>
            </tr>
        </thead>
        <tbody>
            {% for row in v1 %}
                 <tr aa="{{ row.nid }}" ab="{{ row.b.id }}">
                     <td>{{ row.hostname }}</td>
                     <td>{{ row.ip }}</td>
                     <td>{{ row.port }}</td>
                     <td>{{ row.b.caption }}</td>
                     <td>{{ row.b.code }}</td>
                 </tr>
            {% endfor %}
        </tbody>
    </table>
</body>
</html>
templates/host.html

效果图：

一对多跨表操作（第二种，第三种）：

def host(request):
    v1 = models.Host.objects.filter(nid__gt=0)
    for row in v1:
        print(row.nid,row.hostname,row.ip,row.port,row.b_id,row.b.id,row.b.caption,row.b.code,sep='	')

    v2 = models.Host.objects.filter(nid__gt=0).values('nid','hostname','b_id','b__caption') #获取到的值为字典
    # print(v2) 
    for row in v2:
        print(row['nid'],row['hostname'],row['b_id'],row['b__caption'])

    v3 = models.Host.objects.filter(nid__gt=0).values_list('nid','hostname','b_id','b__caption') #获取到的值为元组
    # #print(v3)
    for row in v3:
         print(row)

    # return HttpResponse('你好')
    return render(request,'host.html',{'v1': v1, 'v2':v2 ,'v3':v3})
app01/views.py

print输出结果：

刷新:http://127.0.0.1:8000/host/ 

模拟对话框增加一对多数据示例

from django.shortcuts import render,HttpResponse,redirect
from app01 import models
# Create your views here.

def business(requset):
    v1 = models.Business.objects.all()
    #QuerySet
    #[obj(id,caption,code),obj(id,caption,code),obj(id,caption,code)]

    v2 = models.Business.objects.all().values('id','caption')
    # QuerySet
    # [{'id':1,'caption':'苹果'},{'id':2,'caption':''香蕉}，{'id':3,'caption':'菠萝'}，{'id':4,'caption':'梨子'}]

    v3 = models.Business.objects.all().values_list('id','caption')
    # QuerySet
    # [(0,苹果)，(2,香蕉)]
    return render(requset,'business.html',{'v1':v1,'v2':v2,'v3':v3})


def host(request):
    if request.method == 'GET':
        v1 = models.Host.objects.filter(nid__gt=0)
        v2 = models.Host.objects.filter(nid__gt=0).values('nid','hostname','b_id','b__caption')
        v3 = models.Host.objects.filter(nid__gt=0).values_list('nid','hostname','b_id','b__caption')

        b_list= models.Business.objects.all()

        return render(request,'host.html',{'v1': v1, 'v2':v2 , 'v3':v3 ,'b_list':b_list})

    elif request.method == 'POST':
        h = request.POST.get('hostname')
        i = request.POST.get('ip')
        p = request.POST.get('port')
        b = request.POST.get('b_id')
        # models.Host.objects.create(hostname=h,
        #                            ip=i,
        #                            port=p,
        #                            b=models.Business.objects.get(id=b)
        #                            )
        models.Host.objects.create(hostname=h,
                                   ip=i,
                                   port=p,
                                   b_id=b,
                                    )
        return redirect('/host')   #以get分方式重新访问http://127.0.0.1:8000/host/
app01/views.py
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .hide{
            display: none;
        }
        .shade{
            position: fixed;
            top: 0;
            right:0 ;
            left: 0;
            bottom: 0;
            background: black;
            opacity: 0.6;
            z-index: 100;
        }
        .add-modal{
            position: fixed;
            height: 300px;
             400px;
            top: 100px;
            left: 50%;
            z-index: 101;
            border: 1px solid red;
            background: white;
            margin-left: -200px;
        }
    </style>
</head>
<body>
    <h1>主机列表（列表）</h1>
    <div>
        <input id="add_host" type="button" value="添加"/>    <!--模态对话框-->
    </div>
    <table border="1">

        <thead>
            <tr>
                <th>主机序号</th>
                <th>主机名字</th>
                <th>IP</th>
                <th>端口</th>
                <th>业务线名称</th>
            </tr>
        </thead>
        <tbody>
            {% for row in v1 %}
                <tr aa="{{ row.nid }}" ab="{{ row.b.id }}" ac="{{ row.b.code }}">
                    <td>{{ forloop.counter }}</td>
                    <td>{{ row.hostname }}</td>
                    <td>{{ row.ip }}</td>
                    <td>{{ row.port }}</td>
                    <td>{{ row.b.caption }}</td>
                </tr>
            {% endfor %}
        </tbody>
    </table>
    <h1>主机列表（字典）</h1>
    <table border="1">
        <thead>
        <tr>
            <th>主机名字</th>
            <th>业务线名称</th>
        </tr>
        </thead>
        <tbody>
        {% for row in v2 %}
            <tr aa="{{ row.nid }}" ab="{{ row.b__id }}">
                <td>{{ row.hostname }}</td>
                <td>{{ row.b__caption }}</td>
            </tr>
        {% endfor %}
        </tbody>
    </table>
    </table>
    <h1>主机列表（元组）</h1>
    <table border="1">
        <thead>
        <tr>
            <th>主机名字</th>
            <th>业务线名称</th>
        </tr>
        </thead>
        <tbody>
        {% for row in v3 %}
            <tr aa="{{ row.0 }}" ab="{{ row.2}}">
                <td>{{ row.1 }}</td>
                <td>{{ row.3 }}</td>
            </tr>
        {% endfor %}
        </tbody>
    </table>


    <div class="shade hide"></div>               <!--遮罩层，全屏-->
    <div class="add-modal hide">                 <!--弹出框-->
        <form method="POST" action="/host/">    <!--编辑弹出框内容-->
            <div class="group">
                <input type="text" placeholder="主机名" name="hostname"/>
            </div>

            <div class="group">
                <input type="text" placeholder="IP" name="ip"/>
            </div>

            <div class="group">
                <input type="text" placeholder="端口" name="port"/>
            </div>

            <div class="group">
                <select name="b_id">
                    {% for op in b_list %}
                    <option value="{{ op.id }}">{{ op.caption }}</option>
                    {% endfor %}
                </select>
            </div>

            <input type="submit" value="提交"/>
            <input id="cancel" type="button" value="取消"/>
        </form>
    </div>

    <script src="/static/jquery-1.12.4.js"></script>    <!--JS文件-->
    <script>
        $(function () {                                     <!--页面框架加载完成-->

            $('#add_host').click(function () {              <!--绑定事件-->
                $('.shade,.add-modal').removeClass('hide'); <!--点击添加按钮，呼出遮罩层与弹出框-->
            });

            $('#cancel').click(function () {
                $('.shade,.add-modal').addClass('hide');
            });
            
        })
    </script>
</body>
</html>
templates/host.html

新增static/jquery-1.12.4.js 文件

https://files.cnblogs.com/files/dalyday/jquery-1.12.4.js

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原文地址：https://www.cnblogs.com/dalyday/p/8891238.html