Django: 操作错误 没有这个表
我正在我的Django项目中构建一个相对简单的应用程序,叫做research,它使用了Django-CMS。(这是我第一次从头开始尝试做一个项目/应用程序。)它的主要目的是存储各种知识资产(比如研究人员写的文章、书籍等)。
问题是,当我在浏览器中输入 /research/
时,出现了一个错误,提示 table 'research_journal' doesn't exist ("no such table")
,意思是说找不到这个表。
我使用的是Django 1.6.5,并且数据库是sqlite3。
我查看了 python manage.py sql research
的结果:
BEGIN;
CREATE TABLE "research_researchbase" (
"id" integer NOT NULL PRIMARY KEY,
"pub_date" datetime NOT NULL,
"authors" varchar(200) NOT NULL,
"year" varchar(25) NOT NULL,
"title" varchar(200) NOT NULL,
"subtitle" varchar(200) NOT NULL,
"image_id" integer NOT NULL REFERENCES "filer_image" ("file_ptr_id"),
"link" varchar(200) NOT NULL
)
;
CREATE TABLE "research_journal" (
"researchbase_ptr_id" integer NOT NULL PRIMARY KEY REFERENCES "research_researchbase" ("id"),
"journal" varchar(200) NOT NULL,
"abstract" text NOT NULL,
"citation" varchar(200) NOT NULL
)
;
CREATE TABLE "research_encyclopedia_chapter" (
"researchbase_ptr_id" integer NOT NULL PRIMARY KEY REFERENCES "research_researchbase" ("id"),
"encyclopedia" varchar(200) NOT NULL,
"publisher" varchar(200) NOT NULL,
"summary" varchar(200) NOT NULL
)
;
CREATE TABLE "research_book" (
"researchbase_ptr_id" integer NOT NULL PRIMARY KEY REFERENCES "research_researchbase" ("id"),
"publisher" varchar(200) NOT NULL,
"summary" varchar(200) NOT NULL
)
;
COMMIT;
我运行了 python manage.py migrate research
,结果是:
/Users/XXX/Documents/repos/sfs/env/lib/python2.7/site-packages/app_data/fields.py:2: DeprecationWarning: django.utils.simplejson is deprecated; use json instead.
from django.utils import simplejson as json
Running migrations for research:
- Nothing to migrate.
- Loading initial data for research.
Installed 0 object(s) from 0 fixture(s)
我还运行了 python manage.py syncdb
,得到的结果是:
Syncing...
Creating tables ...
Installing custom SQL ...
Installing indexes ...
Installed 0 object(s) from 0 fixture(s)
Synced:
> djangocms_admin_style
> django.contrib.auth
> django.contrib.contenttypes
> django.contrib.sessions
> django.contrib.admin
> django.contrib.sites
> django.contrib.sitemaps
> django.contrib.staticfiles
> django.contrib.messages
> mptt
> south
> sekizai
> django_select2
> hvad
Not synced (use migrations):
- djangocms_text_ckeditor
- cms
- menus
- djangocms_style
- djangocms_column
- djangocms_file
- djangocms_flash
- djangocms_googlemap
- djangocms_inherit
- djangocms_link
- djangocms_picture
- djangocms_teaser
- djangocms_video
- reversion
- polls
- djangocms_polls
- aldryn_blog
- easy_thumbnails
- filer
- taggit
- research
(use ./manage.py migrate to migrate these)
这是我的 models.py
文件:
from django.db import models
from django.utils import timezone
from filer.fields.image import FilerImageField
import datetime
class ResearchBase(models.Model):
pub_date = models.DateTimeField('date published')
authors = models.CharField(max_length=200)
year = models.CharField(max_length=25)
title = models.CharField(max_length=200)
subtitle = models.CharField(max_length=200, blank=True)
image = FilerImageField()
link = models.CharField(max_length=200, blank=True)
def __unicode__(self):
return self.title
def was_published_recently(self):
return self.pub_date >= timezone.now() - datetime.timedelta(days=1)
class Journal(ResearchBase):
journal = models.CharField(max_length=200)
abstract = models.TextField()
citation = models.CharField(max_length=200)
class Encyclopedia_Chapter(ResearchBase):
encyclopedia = models.CharField(max_length=200)
publisher = models.CharField(max_length=200)
summary = models.CharField(max_length=200)
class Book(ResearchBase):
publisher = models.CharField(max_length=200)
summary = models.CharField(max_length=200)
这是我的 views.py
文件(注意我通过render传递了两个对象,暂时忽略我还没有把Books类包含进来):
from django.shortcuts import render, get_object_or_404
from django.http import HttpResponse, Http404
from django.template import RequestContext, loader
from research.models import Journal, Encyclopedia_Chapter, Book
def research_index(request):
latest_journal_list = Journal.objects.order_by('-pub_date')[:5]
latest_chapter_list = Encyclopedia_Chapter.objects.order_by('-pub_date')[:5]
context = {
'latest_journal_list': latest_journal_list,
'latest_chapter_list': latest_chapter_list
}
return render(request, 'research/index.html', context)
def journal_detail(request, journal_id):
journal = get_object_or_404(Journal, pk=journal_id)
return render(request, 'research/journal_detail.html', {'journal': journal})
def chapter_detail(request, chapter_id):
chapter = get_object_or_404(Encyclopedia_Chapter, pk=chapter_id)
return render(request, 'research/chapter_detail.html', {'chapter': chapter})
这是应用程序的 url.py
文件:
from django.conf.urls import patterns, url
from research import views
urlpatterns = patterns('',
url(r'^$', views.research_index, name='research'),
url(r'^(?P<journal_id>\d+)/$', views.journal_detail, name='journal_detail'),
url(r'^(?P<chapter_id>\d+)/$', views.chapter_detail, name='chapter_detail'),
)
这是 index.html
模板:
{% extends 'research/base.html' %}
{% block research_content %}
<div class="container">
<div class="row featurette">
<h3 id="research">Peer-reviewed Journal Articles</h3>
{% if latest_journal_list %}
<ul id="research">
{% for journal in latest_journal_list %}
<li id="research">
<img src="{{ journal.image.url }}" id="research">
<h4>{{ journal.journal }}</h4>
<h5>{{ journal.title }}</h5>
<a href="{% url 'research:journal_detail' journal.id %}">Read More</a>
</li>
{% endfor %}
</ul>
{% else %}
<p>No journals are available.</p>
{% endif %}
</div>
<div class="row featurette">
<h3 id="research">Encyclopedia Chapters</h3>
{% if latest_chapter_list %}
<ul id="research">
{% for chapter in latest_chapter_list %}
<li id="research">
<img src="{{ chapter.image.url }}" id="research">
<h4>{{ chapter.journal }}</h4>
<h5>{{ chapter.title }}</h5>
<a href="{% url 'research:chapter_detail' chapter.id %}">Read More</a>
</li>
{% endfor %}
</ul>
{% else %}
<p>No encyclopedia chapters are available.</p>
{% endif %}
</div>
</div>
{% endblock %}
如果这有帮助的话,这是我的 cms_app.py
文件:
from cms.app_base import CMSApp
from cms.apphook_pool import apphook_pool
from django.utils.translation import ugettext_lazy as _
class ResearchApp(CMSApp):
name = _("Research App")
urls = ["research.urls"]
app_name = "research"
apphook_pool.register(ResearchApp)
19 个回答
这个问题可能通过运行迁移来解决。
python manage.py makemigrations
这条命令是用来创建迁移文件的。python manage.py migrate
这条命令是用来应用这些迁移文件,把你的数据库更新到最新的状态。
每次你在 models.py
文件中做了修改后,都要执行上面的操作。
如果有人发现上面提到的建议:
python manage.py makemigrations
python manage.py migrate
python manage.py migrate --run-syncdb
不管用,你可能需要在应用程序的目录里新建一个叫做 "migrations
" 的文件夹,并且创建一个空的 __init__.py
文件。
如果你在使用django 1.10,可能需要运行这个命令:python manage.py makemigrations appname
。
使用:
python manage.py migrate --run-syncdb
正如Benyamin Jafari在这条评论中提到的:
--run-syncdb
- 为没有迁移的应用程序创建表。
另外,不要忘记指定应用程序的路径。例如:
python manage.py makemigrations app
python manage.py migrate app
看起来我在迁移数据的时候遇到了一些问题。
我运行了 ./manage.py schemamigration research --auto
这个命令,发现很多字段没有设置默认值。
于是,我接着运行了 ./manage.py schemamigration research --init
,然后又运行了 ./manage.py migrate research
。
从那之后重新启动服务器就解决了问题!