添加SlugField字段类型的问题（Django 1.6.3）

Question

我想和你分享这个案子：

我有模型Albums，Artists和Tracks

• 一个 Artist可能很多 Albums
• 一个 Album可能很多 Tracks
• 许多 Tracks位于一个 Album内（也可能 ManyToMany ）。

在我想要的Albums模型中添加SlugField类型的字段。这是以下内容：

from django.db import models
from artists.models import Artists

    class Album(models.Model):
        title = models.CharField(max_length=255)
        cover = models.ImageField(upload_to='albums') 
        slug = models.SlugField(max_length=100)
        artist = models.ForeignKey(Artists)

        def __unicode__(self):
            return self.title

我在南方进行迁移：

(myvenv)➜  myvenv  ./manage.py syncdb

Syncing...
Creating tables ...
Installing custom SQL ...
Installing indexes ...
Installed 0 object(s) from 0 fixture(s)

Synced:
> django.contrib.admin
> django.contrib.auth
> django.contrib.contenttypes
> django.contrib.sessions
> django.contrib.messages
> django.contrib.staticfiles
> south
> albums

Not synced (use migrations):
- django_extensions
- djcelery
- tracks
- artists
- userprofiles
(use ./manage.py migrate to migrate these)

(myenv)➜  myenv  ./manage.py convert_to_south albums

Creating migrations directory at '/home/bgarcial/workspace/myenv/sfotipy/albums/migrations'...
Creating __init__.py in '/home/bgarcial/workspace/myenv/sfotipy/albums/migrations'...
+ Added model albums.Album
Created 0001_initial.py. You can now apply this migration with: ./manage.py migrate albums
- Soft matched migration 0001 to 0001_initial.
Running migrations for albums:
- Nothing to migrate.
- Loading initial data for albums.
Installed 0 object(s) from 0 fixture(s)

App 'albums' converted. Note that South assumed the application's models matched the   database
(i.e. you haven't changed it since last syncdb); if you have, you should delete  the  albums/migrations directory, revert models.py so it matches the database, and try again.

(myenv)➜  myenv  ./manage.py migrate albums         

Running migrations for albums:
- Nothing to migrate.
- Loading initial data for albums.
Installed 0 object(s) from 0 fixture(s) 

如果我输入命令./manage.py sqlall，相册模型已经出现在数据库中的slug字段

(Sfoti.py)➜  sfotipy  ./manage.py sqlall albums
BEGIN;
CREATE TABLE "albums_album" (
    "id" integer NOT NULL PRIMARY KEY,
    "title" varchar(255) NOT NULL,
    "cover" varchar(100) NOT NULL,
    "slug" varchar(100) NOT NULL,
    "artist_id" integer NOT NULL REFERENCES "artists_artists" ("id")
);
CREATE INDEX "albums_album_f52cfca0" ON "albums_album" ("slug");
CREATE INDEX "albums_album_7904f807" ON "albums_album" ("artist_id");
COMMIT; 

但是，当我进入数据库，直接进入Django带给我的数据库结构时，我发现slug字段无效......这可以在这个网址中详细说明https://cldup.com/-F9SQ2D3W8.jpeg

为了测试这个slu works的作用，我创建了url＆＃34;专辑＆＃34;指向AlbumListView基于类的视图

from django.conf.urls import patterns, url
from artists.views import AlbumListView

urlpatterns = patterns('',
    url(r'^albums/$', AlbumListView.as_view(), name='album_list'),
    url(r'^albums/(?P<artist>[\w\-]+)/$', AlbumListView.as_view(), name='album_list'),
)

基于类的视图AlbumListView如下：在此我定义了一个 queryset ，用于恢复艺术家的相册，使用 kwargs 变量是如何获取

的方式

class AlbumListView(ListView):
    model = Album
    template_name = 'album_list.html'

    def get_queryset(self):
        if self.kwargs.get('artist'):
            queryset = self.model.objects.filter(artist__slug=self.kwargs['artist'])
        else:
            queryset = super(AlbumListView, self).get_queryset()
        return queryset

当我在浏览器中转到视图/相册时，我会看到以下消息：

no such column: albums_album.slug

这是我浏览器中的错误图片，请查看此网址：

我的问题是什么？为什么迁移不起作用？ 谢谢你的指导:)

Answer 1

您似乎已将slug添加到模型 AFTER 运行syncdb并之前运行convert_to_south。特别是关于你的案例，南方开发者在控制台中显示一条警告信息：

  

请注意，南方假设应用程序的模型与之匹配   数据库（即自上次syncdb以来你没有改变它）;如果你有，   你应该删除专辑/迁移目录，还原models.py所以   它匹配数据库，然后再试一次。

要解决问题，您应该：

• 从专辑中删除SlugField（在您的控制台输出中查找，您也应该删除艺术家）
• 从相册应用
中删除迁移文件夹
• 运行./manage.py convert_to_south相册
• 运行./manage.py迁移相册
• 添加SlugField
• 运行./manage.py架构移动相册--auto（将默认值指定为''）
• 运行./manage.py迁移相册
• 利润！