python django 实例调用save保存数据的时候报错 object has no attribute '_state'?大佬们怎么解决啊?

报错 object has no attribute '_state'?大佬们怎么解决啊?

1个回答

qq_36826233
qq_36826233 找到原因了,是因为执行了_dict_ = **kwargs,导致对象_state属性被覆盖了
8 个月之前 回复
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"/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/django/db/migrations/executor.py", line 110, in migrate self.apply_migration(states[migration], migration, fake=fake, fake_initial=fake_initial) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/django/db/migrations/executor.py", line 147, in apply_migration state = migration.apply(state, schema_editor) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/django/db/migrations/migration.py", line 115, in apply operation.database_forwards(self.app_label, schema_editor, old_state, project_state) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/django/db/migrations/operations/models.py", line 59, in database_forwards schema_editor.create_model(model) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/django/db/backends/base/schema.py", line 286, in create_model self.execute(sql, params or None) File 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"/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/django/db/backends/mysql/base.py", line 124, in execute return self.cursor.execute(query, args) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/cursors.py", line 170, in execute result = self._query(query) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/cursors.py", line 328, in _query conn.query(q) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/connections.py", line 517, in query self._affected_rows = self._read_query_result(unbuffered=unbuffered) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/connections.py", line 732, in _read_query_result result.read() File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/connections.py", line 1075, in read first_packet = self.connection._read_packet() File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/connections.py", line 684, in _read_packet packet.check_error() File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/protocol.py", line 220, in check_error err.raise_mysql_exception(self._data) File "/home/huangdonglin/.virtualenvs/django_py3/lib/python3.6/site-packages/pymysql/err.py", line 109, in raise_mysql_exception raise errorclass(errno, errval)
django 迁移数据库 报错,求大神指教!
不知道为什么,创建一个新的app,迁移数据库就报错了,报错信息如下,求大神帮帮忙 ![图片说明](https://img-ask.csdn.net/upload/201911/22/1574414856_903196.png)
求解!!!!!请问怎样调用在django自带的数据库中新建立的数据表?
下面是view.py 的一部分代码,我想把用户输入的数据存到“书籍信息表”,但是 不知道哪里出问题了,django自带了sqlite3数据库,要使用在sqlite3里新建立的表要不要先连接,求解!!! 数据表分别有:用户信息表、书籍信息表、管理员信息表 from django.shortcuts import render, redirect from .models import 用户信息表, 书籍信息表, 管理员信息表 from django.contrib.auth import authenticate, login, logout from django.contrib.auth.models import User from django.contrib import auth def sell(request): if request.method == ‘GET’: return render(request, ‘我要卖.html’) elif request.method == ‘POST’: 书名 = request.POST【‘书名’】 作者 = request.POST【‘作者’】 try: ISDN码 = request.POST【‘ISDN’】 出版社 = request.POST【‘出版社’】 卖家联系方式 = request.POST【‘电话’】 product = 书籍信息表() product.book_name = 书名 product.author = 作者 product.isdn码 = ISDN码 product.publisher = 出版社 product.Tel = 卖家联系方式 product.save() return redirect(‘主页’) except Exception as err: return render(redirect, ‘我要卖.html’, {‘错误’: ‘请填写完整信息!’})
python3的Django中的表单上传图片报错
python的django3的表单上传图片报错: **dictionary update sequence element #0 has length 1; 2 is required** 表单如下: ![图片说明](https://img-ask.csdn.net/upload/201901/18/1547754622_629551.png) view中的uploadHandle视图: **def uploadHandle(request): return HttpResponse('hello')** 点击上传之后就报如上所述的错误。请教各位大佬这是什么原因造成的? 望各位大佬不吝赐教。 小白先在此跪谢了!!! 补充说明:python版本3.71,django版本2.15
django中怎样调用sql数据库中的存储过程?存储过程返回一个表,可以用模型类查询吗?
如题,django中怎样调用sql数据库中的存储过程?存储过程返回一个表,可以用模型类查询吗?
django中重写logging.Handle的emit,在里面实现日志的保存,但是在配置时一直报错,好像不能配置自定义的handlers
现在common的view下写了一个MyHandle类,重写emit方法 ``` class MyHandle(logging.Handler): """ 输出日志到队列 """ def emit(self, record): insert_logging.apply_async(args=[self.format(record)], queue=settings.RABBITMQ_QUEUE) ``` 此代码放在celery文件中,想通过celery来实现日志写入队列,之后再做处理 ![图片说明](https://img-ask.csdn.net/upload/202001/19/1579415564_177923.jpg) 但是我的消费者写在tasks文件中 然后再配置中加上handle,保证在每次访问的时候都会写入到队列 ![图片说明](https://img-ask.csdn.net/upload/202001/19/1579415680_323635.jpg) 结果在启动的时候就会报错,app没加载,因为tasks里面会加载到一些模型类等等。 最大的问题就是如果自定义了Handle,不知道这个handle该如何配置,才能不会在项目启动时发生冲突 ![图片说明](https://img-ask.csdn.net/upload/202001/19/1579415103_30076.png) 上图是django的配置,里面是自定义了一个handle
大神求助。Django。python manage crontab add/remove/show报错
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python+django能够同时使用mongodb和mysql两种数据库引擎吗?
各位朋友们好,我原来做一个项目:因为表没有关联,所以用的是非关系型数据库mongodb,项目开发环境用的是python+django,部署在ubuntu上。当时用了pymongo做python和mongodb的连接,用mongoengine做了django与mongodb的连接。 现在来了新的需求,表之间有关联,因此我准备添加一个mysql数据库。 请教各位朋友们,django展示网页的时候,能够同时展示mongodb中表的内容和mysql中表的内容吗?settings.py中应该如何配置数据库呢? 希望朋友们能指点一下,万分感谢。
问个有关django+heroku的问题
``` Traceback (most recent call last): File "/app/.heroku/python/lib/python3.6/site-packages/django/db/backends/utils.py", line 64, in execute return self.cursor.execute(sql, params) psycopg2.errors.UndefinedTable: relation "auth_user" does not exist LINE 1: ...user"."is_active", "auth_user"."date_joined" FROM "auth_user... The above exception was the direct cause of the following exception: Traceback (most recent call last): File "manage.py", line 10, in <module> execute_from_command_line(sys.argv) File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/__init__.py", line 351, in execute_from_command_line utility.execute() File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/__init__.py", line 325, in execute django.setup() File "/app/.heroku/python/lib/python3.6/site-packages/django/__init__.py", line 18, in setup apps.populate(settings.INSTALLED_APPS) File "/app/.heroku/python/lib/python3.6/site-packages/django/apps/registry.py", line 108, in populate app_config.import_models(all_models) File "/app/.heroku/python/lib/python3.6/site-packages/django/apps/config.py", line 198, in import_models self.models_module = import_module(models_module_name) File "/app/.heroku/python/lib/python3.6/importlib/__init__.py", line 126, in import_module return _bootstrap._gcd_import(name[level:], package, level) File "<frozen importlib._bootstrap>", line 978, in _gcd_import File "<frozen importlib._bootstrap>", line 961, in _find_and_load File "<frozen importlib._bootstrap>", line 950, in _find_and_load_unlocked File "<frozen importlib._bootstrap>", line 655, in _load_unlocked File "<frozen importlib._bootstrap_external>", line 678, in exec_module File "<frozen importlib._bootstrap>", line 205, in _call_with_frames_removed File "/app/learning_logs/models.py", line 7, in <module> class Topic(models.Model): File "/app/learning_logs/models.py", line 8, in Topic choices=Help().choices() File "/app/learning_logs/help.py", line 9, in choices for user in users: File "/app/.heroku/python/lib/python3.6/site-packages/django/db/models/query.py", line 162, in __iter__ self._fetch_all() File "/app/.heroku/python/lib/python3.6/site-packages/django/db/models/query.py", line 965, in _fetch_all self._result_cache = list(self.iterator()) File "/app/.heroku/python/lib/python3.6/site-packages/django/db/models/query.py", line 238, in iterator results = compiler.execute_sql() File "/app/.heroku/python/lib/python3.6/site-packages/django/db/models/sql/compiler.py", line 840, in execute_sql cursor.execute(sql, params) File "/app/.heroku/python/lib/python3.6/site-packages/django/db/backends/utils.py", line 64, in execute return self.cursor.execute(sql, params) File "/app/.heroku/python/lib/python3.6/site-packages/django/db/utils.py", line 97, in __exit__ six.reraise(dj_exc_type, dj_exc_value, traceback) File "/app/.heroku/python/lib/python3.6/site-packages/django/utils/six.py", line 658, in reraise raise value.with_traceback(tb) File "/app/.heroku/python/lib/python3.6/site-packages/django/db/backends/utils.py", line 64, in execute return self.cursor.execute(sql, params) django.db.utils.ProgrammingError: relation "auth_user" does not exist LINE 1: ...user"."is_active", "auth_user"."date_joined" FROM "auth_user... ``` 在heroku bash操作makemigrations,migrate中出现的错误 在本地用这些没问题 settings.py ``` """ Django settings for learning_log project. Generated by 'django-admin startproject' using Django 1.8.5. For more information on this file, see https://docs.djangoproject.com/en/1.8/topics/settings/ For the full list of settings and their values, see https://docs.djangoproject.com/en/1.8/ref/settings/ """ # Build paths inside the project like this: os.path.join(BASE_DIR, ...) import os import django_heroku BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__))) # Quick-start development settings - unsuitable for production # See https://docs.djangoproject.com/en/1.8/howto/deployment/checklist/ # SECURITY WARNING: keep the secret key used in production secret! SECRET_KEY = 'o47!#$sbu_&=)pnbk63ra!hjbx@+pc=2j42cf(&mx82&hs&ph_' # SECURITY WARNING: don't run with debug turned on in production! DEBUG = True ALLOWED_HOSTS = [] # Application definition INSTALLED_APPS = ( 'whitenoise.runserver_nostatic', 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', #my app 'learning_logs', 'users', #other app 'bootstrap3', ) MIDDLEWARE = [ 'django.middleware.clickjacking.XFrameOptionsMiddleware', 'whitenoise.middleware.WhiteNoiseMiddleware', ] MIDDLEWARE_CLASSES = ( 'django.contrib.sessions.middleware.SessionMiddleware', 'django.middleware.common.CommonMiddleware', 'django.middleware.csrf.CsrfViewMiddleware', 'django.contrib.auth.middleware.AuthenticationMiddleware', 'django.contrib.auth.middleware.SessionAuthenticationMiddleware', 'django.contrib.messages.middleware.MessageMiddleware', 'django.middleware.clickjacking.XFrameOptionsMiddleware', 'django.middleware.security.SecurityMiddleware', ) ROOT_URLCONF = 'learning_log.urls' TEMPLATES = [ { 'BACKEND': 'django.template.backends.django.DjangoTemplates', 'DIRS': [], 'APP_DIRS': True, 'OPTIONS': { 'context_processors': [ 'django.template.context_processors.debug', 'django.template.context_processors.request', 'django.contrib.auth.context_processors.auth', 'django.contrib.messages.context_processors.messages', ], }, }, ] WSGI_APPLICATION = 'learning_log.wsgi.application' # Database # https://docs.djangoproject.com/en/1.8/ref/settings/#databases DATABASES = { 'default': { 'ENGINE': 'django.db.backends.sqlite3', 'NAME': os.path.join(BASE_DIR, 'db.sqlite3'), } } # Internationalization # https://docs.djangoproject.com/en/1.8/topics/i18n/ LANGUAGE_CODE = 'en-us' TIME_ZONE = 'UTC' USE_I18N = True USE_L10N = True USE_TZ = True LOGIN_URL = '/users/login/' # Static files (CSS, JavaScript, Images) # https://docs.djangoproject.com/en/1.8/howto/static-files/ STATIC_URL = '/static/' MEDIA_URL = '/media/' MEDIA_ROOT = os.path.join(BASE_DIR, 'media') STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles') if os.getenv('DATABASE_URL') is not None: import dj_database_url DATABASES['default'] = dj_database_url.config() SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https') ALLOWED_HOSTS = ['stark-anchorage-08076.herokuapp.com'] DEBUG = False BASE_DIR = os.path.dirname(os.path.abspath(__file__)) STATICFILES_DIRS = ( os.path.join(BASE_DIR, 'static'), ) django_heroku.settings(locals()) ``` views.py ``` from django.shortcuts import render from .models import Topic, Entry, Root, Suf_Pre_fix from django.http import HttpResponseRedirect, Http404 from django.core.urlresolvers import reverse from .forms import TopicForm, EntryForm, RootForm from django.contrib.auth.decorators import login_required from .help import Help from django.contrib.auth.models import User # Create your views here. def index(request): return render(request, 'learning_logs/index.html') @login_required def topics(request): topics = Topic.objects.order_by('date_added') context = {'topics': topics} return render(request, 'learning_logs/topics.html', context) @login_required def topic(request, topic_id): topic = Topic.objects.get(id=topic_id) entries = topic.entry_set.order_by('-date_added') context = {'topic': topic,'entries': entries} return render(request, 'learning_logs/topic.html', context) @login_required def new_topic(request): if request.method != 'POST': form = TopicForm() else: form = TopicForm(request.POST) if form.is_valid(): new_topic = form.save(commit=False) new_topic.owner = request.user new_topic.edit_able = request.POST.getlist("edit_able") new_topic.save() return HttpResponseRedirect(reverse('learning_logs:topics')) context = {'form': form, 'users':Help().users()} return render(request, 'learning_logs/new_topic.html', context) @login_required def new_entry(request, topic_id): topic = Topic.objects.get(id=topic_id) if request.method != 'POST': form = EntryForm() else: form = EntryForm(data=request.POST) if form.is_valid(): new_entry = form.save(commit=False) new_entry.topic = topic new_entry.edit_able = request.POST.getlist("edit_able") new_entry.save() return HttpResponseRedirect(reverse('learning_logs:topic',args=[topic_id])) context = {'topic':topic, 'form': form, 'users':Help().users()} return render(request, 'learning_logs/new_entry.html', context) @login_required def edit_entry(request, entry_id): entry = Entry.objects.get(id=entry_id) topic = entry.topic if not Help().check_user(request.user,entry.edit_able) or not Help().check_user(request.user,topic.edit_able): raise Http404 if request.method != 'POST': form = EntryForm(instance=entry) else: form = EntryForm(instance=entry, data=request.POST) if form.is_valid(): edit_entry = form.save(commit=False) edit_entry.edit_able = request.POST.getlist("edit_able") edit_entry.save() return HttpResponseRedirect(reverse('learning_logs:topic',args=[topic.id])) context = {'entry': entry, 'topic': topic, 'form': form ,'users':Help().users()} return render(request, 'learning_logs/edit_entry.html', context) @login_required def roots(request): roots = Root.objects.order_by('date_added') context = {'roots': roots} return render(request, 'learning_logs/roots.html', context) def root(request, root_id): root = Root.objects.get(id=root_id) things = root.things.order_by('-date_added') context = {'root':root, 'things':things} return render(request, 'learning_logs/root.html', context) ``` help.py ``` from django.contrib.auth.models import User class Help(): def __init__(self): pass def choices(self): users=User.objects.all() choices=[] a=1 for user in users: choices.append((a,str(user))) a+=1 return choices def check_user(self,user,users): try: str(users).index(str(user)) except: return False else: return True def users(self): users=[] for user in User.objects.all(): users.append(str(user)) return users def test_list(self,list1): for item in list1: print(type(item)) def test_word(self,item): print(item,type(item)) ```
xadmin python django
![图片说明](https://img-ask.csdn.net/upload/201706/11/1497182486_810437.png) ![图片说明](https://img-ask.csdn.net/upload/201706/11/1497182499_34916.png) ![图片说明](https://img-ask.csdn.net/upload/201706/11/1497182538_524367.png) ![图片说明](https://img-ask.csdn.net/upload/201706/11/1497182544_199483.png) 点击1234这一项然后报错,问题在django中的widgets.py中,如图三的return [value.date(), value.time().replace(microsecond=0)], 这句话我改成下面注释的 return [value,value] 就没错了,但是搜寻了一些文档和GITHub上的源码发现都是上面那句return 请教这里要怎么修改 (不影响这个decompress方法的返回的前提下)
python django web程序 部署相关知识求分享
最近自己在学习python django web程序,现在遇到了部署的问题,不知道该如何选择,也不知道该如何发布,求相关前辈指导,最好是windows平台,谢谢了。
python django models 中的返回值问题
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python django如何对多个表的多条数据进行分页
假设我现在mysql上有两个表,A表和B表, A表中有两个字段一个msgid和一个userid, B表中有三个字段一个id字段和一个msg字段还有一个msgid字段, A表中的userid字段可能存在多条相同的userid值, B表中的msgid也有可能存在多条相同的msgid, 现在要根据A表中的userid查询B表中的msg值, 目前我想的查询逻辑大概是这样的: 先拿到一个userid去A表查询 ,然后遍历查询到的所有值data, 然后在用data相关联的msgid查询所有B表的msg值, 但是想分页就不知道怎么分了 !请大神给解答下!
Java学习的正确打开方式
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