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  • model相关

    链接数据库

     与数据库相关的两条命令：

    1 python manage.py makemigrations    
2 python manage.py migrate

    设置数据库

     mysql：

    单表操作

     1 DATABASES = {
 2 
 3     'default': {
 4 
 5         'ENGINE': 'django.db.backends.mysql',
 6 
 7         'NAME': 'blog',    #你的数据库名称
 8 
 9         'USER': 'root',   #你的数据库用户名
10 
11         'PASSWORD': '', #你的数据库密码
12 
13         'HOST': '', #你的数据库主机，留空默认为localhost
14 
15         'PORT': '3306', #你的数据库端口
16 
17     }
18 
19 }
    若出现连接错误：：

    在models.py里边建立模型

     

    关于数据类型的说明：

     操作相关

    导入

    增：

    1 增加：
2 （1）bookobj=models.Book(title='一本小说'，aithor='yuan')
3         bookobj.save()
4 
5 （2）abook=models.Book.create(title='一本小说'，....)
6 abook是返回的一个对象

    查：

    　　

    1 查询全部：models.Book.objects.all()
2 查询符合条件的：models.Book.objects.filter(bid=sel_id)
3 符合条件的第一条：models.Book.objects.filter(bid=sel_id).first()

    改

     1 models.Book.objects.filter(bid=1).update( name='hahah')

    修改哪一个字段改哪一个字段

    删

     1 models.Book.objects.filter(bid=del_id).delete() 

    查询方法API：
     1 # 查询方法API：
 2 
 3 
 4     # 1  all： models.表名.objects.all()
 5     # 
 6     book_all=models.Book.objects.all()  # 结果是querySet集合    [model对象，....]
 7     #print(book_all) # <QuerySet [<Book: Book object>, <Book: Book object>, <Book: Book object>]>
 8 
 9     # 2 filter： models.表名.objects.filter() # 结果是querySet集合    [model对象，....]
10 
11     # ret1=models.Book.objects.filter(author="yuan") # # <QuerySet [<Book: 追风筝的人>, <Book: asd>]>
12     #ret2=models.Book.objects.filter(nid=1) # <QuerySet [<Book: yuan>]>
13     # ret2=models.Book.objects.filter(author="yuan",price=123) # <QuerySet [<Book: yuan>]>
14     # print(ret2)
15 
16     # 3 get  models.表名.objects.get()   # model对象
17 
18     # ret3=models.Book.objects.get(author="yuan")
19     # print(ret3.price)
20 
21 
22     # exclude : 排除条件
23     # ret4=models.Book.objects.exclude(author="yuan")
24     # print(ret4)
25 
26     # values方法
27     # ret=models.Book.objects.filter(author="yuan").values("title","price")
28     # print(ret)# <QuerySet [{'title': '追风筝的人', 'price': Decimal('99.00')}, {'title': 'asd', 'price': Decimal('123.00')}]>
29 
30     # ret = models.Book.objects.filter(author="yuan").values_list("title", "price")
31     # print(ret) # <QuerySet [('追风筝的人', Decimal('99.00')), ('asd', Decimal('123.00'))]>
32 
33     # ret=models.Book.objects.filter(author="yuan").values("author").distinct()
34     # print(ret)
35 
36     # count方法
37     # ret=models.Book.objects.filter(author="yuan").count()
38     # print(ret)
39 
40     # first 方法
41     # ret = models.Book.objects.all().first()
42     # print(ret)
43 
44     # exists方法
45     # if models.Book.objects.all().exists():
46     #     print("exists")
47     # else:
48     #     print("nothing")
49 
50 
51 
52     ret=models.Book.objects.filter(price__gt=100)
53     ret=models.Book.objects.filter(price__gte=99) # 大于等于
54 
55     #ret=models.Book.objects.filter(publishDate__year=2017,publishDate__month=10)
56     #ret=models.Book.objects.filter(author__startswith="张")

     1 # 查询方法API：
 2 
 3 
 4     # 1  all： models.表名.objects.all()
 5     # 
 6     book_all=models.Book.objects.all()  # 结果是querySet集合    [model对象，....]
 7     #print(book_all) # <QuerySet [<Book: Book object>, <Book: Book object>, <Book: Book object>]>
 8 
 9     # 2 filter： models.表名.objects.filter() # 结果是querySet集合    [model对象，....]
10 
11     # ret1=models.Book.objects.filter(author="yuan") # # <QuerySet [<Book: 追风筝的人>, <Book: asd>]>
12     #ret2=models.Book.objects.filter(nid=1) # <QuerySet [<Book: yuan>]>
13     # ret2=models.Book.objects.filter(author="yuan",price=123) # <QuerySet [<Book: yuan>]>
14     # print(ret2)
15 
16     # 3 get  models.表名.objects.get()   # model对象
17 
18     # ret3=models.Book.objects.get(author="yuan")
19     # print(ret3.price)
20 
21 
22     # exclude : 排除条件
23     # ret4=models.Book.objects.exclude(author="yuan")
24     # print(ret4)
25 
26     # values方法
27     # ret=models.Book.objects.filter(author="yuan").values("title","price")
28     # print(ret)# <QuerySet [{'title': '追风筝的人', 'price': Decimal('99.00')}, {'title': 'asd', 'price': Decimal('123.00')}]>
29 
30     # ret = models.Book.objects.filter(author="yuan").values_list("title", "price")
31     # print(ret) # <QuerySet [('追风筝的人', Decimal('99.00')), ('asd', Decimal('123.00'))]>
32 
33     # ret=models.Book.objects.filter(author="yuan").values("author").distinct()
34     # print(ret)
35 
36     # count方法
37     # ret=models.Book.objects.filter(author="yuan").count()
38     # print(ret)
39 
40     # first 方法
41     # ret = models.Book.objects.all().first()
42     # print(ret)
43 
44     # exists方法
45     # if models.Book.objects.all().exists():
46     #     print("exists")
47     # else:
48     #     print("nothing")
49 
50 
51 
52     ret=models.Book.objects.filter(price__gt=100)
53     ret=models.Book.objects.filter(price__gte=99) # 大于等于
54 
55     #ret=models.Book.objects.filter(publishDate__year=2017,publishDate__month=10)
56     #ret=models.Book.objects.filter(author__startswith="张")
    相关的API部分

    多表查询

    建立多表，以图书管理系统为例

     1 from django.db import models
 2 
 3 # Create your models here.
 4 class Book(models.Model):
 5     #book表
 6     bid=models.AutoField(primary_key=True)
 7 
 8     title=models.CharField(max_length=42)
 9 
10     publishDate=models.DateField()
11 
12     price=models.DecimalField(max_digits=5,decimal_places=2)
13 
14     author=models.ManyToManyField('Author')
15 
16     press = models.ForeignKey('Press')
17     # read_many = models.OneToOneField('Read_many')
18     def  __str__(self):
19         return self.title
20 
21 
22 class Author(models.Model):
23     #作者表
24     name=models.CharField(max_length=32)
25     tel=models.IntegerField()
26     # press=models.OneToOneField(to='Press')
27     def __str__(self):
28         return self.name
29 
30 class Press(models.Model):
31     #出版社表
32     press_name=models.CharField(max_length=32)
33     press_addr=models.CharField(max_length=32)
34     def __str__(self):
35         return self.press_name
36 
37 # class Read_many(models.Model):
38 #     #阅读相关表
39 #     wordNum=models.IntegerField(default=0)
40 #     readNum=models.IntegerField(default=0)
    models代码
      1 from django.shortcuts import render,redirect,HttpResponse
  2 from app01 import models
  3 
  4 
  5 import datetime,time
  6 # Create your views here.
  7 def Dashboard(request):
  8     return render(request, 'Dashboard.html')
  9 
 10 def base(request):
 11     return render(request,'base.html')
 12 
 13 def insert_book(request):
 14 
 15     return redirect('/info/')
 16 
 17 
 18 def book_info(request):
 19     book_info_all=models.Book.objects.all()
 20     # try:
 21     #     print('看作者：', book_info_all.first().author.all())
 22     # except Exception:
 23     #     print('这里出错了')
 24     list_name = models.Author.objects.all().values_list('id','name')
 25     # print('作者的名字', list_name)
 26     list_press = models.Press.objects.all().values_list('id','press_name')
 27     # print('出版社：', list_press)
 28     return render(request,'BookInfo.html',{'book_info_all':book_info_all,'list_name':list_name,'list_press':list_press})
 29 
 30 
 31 # def tianjia(request):
 32 #     list_name=models.Author.objects.all().values_list('name')
 33 #     print('作者的名字',list_name)
 34 #     list_press=models.Press.objects.all().values_list('press_name')
 35 #     print('出版社：',list_press)
 36 #     # for i in list_name:
 37 #     #     print(i[0])
 38 #     return render(request,'tianjia.html',{'list_name':list_name,'list_press':list_press})
 39 
 40 
 41 
 42 def tianjia(request):
 43     print('这里是添加的东西',request.POST)
 44     book_obj=models.Book.objects.create(
 45         title=request.POST.get('title'),
 46         publishDate=request.POST.get('date'),
 47         price=request.POST.get('price'),
 48         press_id=request.POST.get('press')
 49     )
 50     # print('title',request.POST.get('title'))
 51     # print('date',request.POST.get('date'))
 52     # print('price',request.POST.get('price'))
 53 
 54     # author_id=request.POST.get('author')
 55     author_id=request.POST.getlist('author')
 56     print('author_id',author_id)
 57     for author_one in author_id:
 58         print('第一' * 10)
 59         print(models.Author.objects.filter(id=author_one))
 60         book_obj.author.add(models.Author.objects.filter(id=int(author_one))[0])
 61         print(models.Author.objects.filter(id=author_one))
 62         # print('第2' * 10,models.Author.objects.filter(id=author_one))
 63     # press_id=request.POST.get('press')
 64     # print('第3' * 10)
 65     # book_obj.press=models.Press.objects.filter(id=press_id)
 66 
 67     return redirect('/book/')
 68 
 69 
 70 
 71 
 72 
 73 def  del_id(request,book_id):
 74     models.Book.objects.filter(bid=book_id).delete()
 75     return redirect('/book/')
 76 
 77 
 78 
 79 def bianji(request,book_id):
 80     edit_info=models.Book.objects.filter(bid=book_id).first()
 81     # print(edit_info.author.all().values_list('id','name'))
 82     eau=edit_info.author.all().values_list('id','name')
 83     item_l=[]
 84     for item_id in eau:
 85         item_l.append(item_id[0])
 86     # print('作者的名字eau',eau)
 87     # print( '66666666666666666+',models.Author.objects.all().values())
 88     list_name=edit_info.author.all().values_list('id','name')
 89     list_name = models.Author.objects.exclude(id__in=item_l).values_list('id','name')
 90     # print('作者的名字', list_name)
 91     list_press = models.Press.objects.exclude(id=edit_info.press_id).values_list('id','press_name')
 92 
 93     return render(request,'info_edit.html',{'edit_info':edit_info,'list_name':list_name,'list_press':list_press,'eau':eau})
 94 
 95 #
 96 def info_edit(request):
 97     book_obj = models.Book.objects.filter(bid=request.POST.get('bid'))
 98     book_obj.update(
 99         title=request.POST.get('title'),
100         publishDate=request.POST.get('date'),
101         price=request.POST.get('price'),
102         press_id=request.POST.get('press')
103     )
104     book_obj[0].author.clear()
105     # for au_id in request.POST.getlist('author'):
106     auobj=models.Author.objects.filter(id__in=request.POST.getlist('author'))
107     for add_obj in auobj:
108         book_obj[0].author.add(add_obj)
109     print('查询出来的',auobj)
110     print('book_obj.authorList',book_obj[0].author.all())
111     # print(request.POST.get('title'))
112     return redirect('/book/')
    View代码
     1 from django.conf.urls import url
 2 from django.contrib import admin
 3 from app01 import views
 4 
 5 urlpatterns = [
 6     url(r'^admin/', admin.site.urls),
 7     url(r'^Dashboard/', views.Dashboard),
 8     url(r'^base/', views.base),
 9     url(r'^book/', views.book_info),
10     url(r'^tianjia/', views.tianjia),
11     url(r'^del/(d+)', views.del_id),
12     url(r'^bianji/(d+)', views.bianji),
13     url(r'^info_edit/', views.info_edit),
14 ]
    urls

    *

    *

    *

    *

    *

    **

    *

    *
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  • 原文地址：https://www.cnblogs.com/xiesibo/p/7731083.html
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