• 【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
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