models.py

Question

要点：我正在关注南方教程。我更改了一个models.py文件，但是当我运行“migrate”时，它不会更新psql表。我不知道为什么不。

我编辑了民意调查/ models.py 我加了一节课，“调查” 我在“问题”中添加了一行来参考调查

models.py

我添加了课程Survey

我在课程问题中添加了这一行：

survey = models.ForeignKey(Survey)

所有其他已经存在（基本上按照django教程）

import datetime
from django.db import models
from django.utils import timezone

# Create your models here.

### Adding the Survey class just now, to practice using South
class Survey(models.Model):
  survey_name = models.CharField(max_length=190)
  pub_date = models.DateTimeField('date published')
  def __unicode__(self): #__str__ instead of __unicode__ if using Python 3, but unicode for python 2
    return self.survey_name
  def was_published_recently(self):
    return self.pub_date >= timezone.now() - datetime.timedelta(days=1)
  was_published_recently.admin_order_field = 'pub_date'
  was_published_recently.boolean = True
  was_published_recently.short_description = 'Published recently?' # for admin site


class Question(models.Model):
  survey = models.ForeignKey(Survey) ### this is a new line based on adding the Survey class above
  question_text = models.CharField(max_length=200)
  pub_date = models.DateTimeField('date published')
  def __unicode__(self): #__str__ instead of __unicode__ if using Python 3, but unicode for python 2
    return self.question_text
  def was_published_recently(self):
    return self.pub_date >= timezone.now() - datetime.timedelta(days=1)
  was_published_recently.admin_order_field = 'pub_date'
  was_published_recently.boolean = True
  was_published_recently.short_description = 'Published recently?' # for admin site


class Choice(models.Model):
  question = models.ForeignKey(Question)
  choice_text = models.CharField(max_length=200)
  votes = models.IntegerField(default=0)
  def __unicode__(self):
    return self.choice_text

终端

我做了schemamigration，它说它添加了模型polls.Survey

（app01）MoriartyMacBookAir13：getstartapp macuser $ vim polls / models.py （app01）MoriartyMacBookAir13：getstartapp macuser $ python manage.py schemamigration民意调查--auto 您不能在没有迁移的应用上使用--auto。尝试 - 初始。（app01）MoriartyMacBookAir13：getstartapp macuser $ sudo python manage.py schemamigration民意调查 - 初始
- 添加了模型民意调查。调查
- 添加了模型民意调查。问题
- 添加了模型民意调查。选择创建0001_initial.py。您现在可以使用以下命令应用此迁移：./ manage.py migrate polls

我仔细检查了psql表中不存在的调查：

(app01)MoriartyMacBookAir13:getstartapp macuser$ heroku pg:psql
---> Connecting to HEROKU_POSTGRESQL_YELLOW_URL (DATABASE_URL)
psql (9.3.5, server 9.3.3)
SSL connection (cipher: DHE-RSA-AES256-SHA, bits: 256)
Type "help" for help.

app01::YELLOW=> \d
                             List of relations
 Schema |                 Name                 |   Type   |     Owner      
--------+--------------------------------------+----------+----------------
 public | account_emailaddress                 | table    | aqolirupsmmmqz
 public | account_emailaddress_id_seq          | sequence | aqolirupsmmmqz
 public | account_emailconfirmation            | table    | aqolirupsmmmqz
 public | account_emailconfirmation_id_seq     | sequence | aqolirupsmmmqz
 public | auth_group                           | table    | aqolirupsmmmqz
 public | auth_group_id_seq                    | sequence | aqolirupsmmmqz
 public | auth_group_permissions               | table    | aqolirupsmmmqz
 public | auth_group_permissions_id_seq        | sequence | aqolirupsmmmqz
 public | auth_permission                      | table    | aqolirupsmmmqz
 public | auth_permission_id_seq               | sequence | aqolirupsmmmqz
 public | auth_user                            | table    | aqolirupsmmmqz
 public | auth_user_groups                     | table    | aqolirupsmmmqz
 public | auth_user_groups_id_seq              | sequence | aqolirupsmmmqz
 public | auth_user_id_seq                     | sequence | aqolirupsmmmqz
 public | auth_user_user_permissions           | table    | aqolirupsmmmqz
 public | auth_user_user_permissions_id_seq    | sequence | aqolirupsmmmqz
 public | discover_author                      | table    | aqolirupsmmmqz
 public | discover_author_id_seq               | sequence | aqolirupsmmmqz
 public | discover_awedio                      | table    | aqolirupsmmmqz
 public | discover_awedio_id_seq               | sequence | aqolirupsmmmqz
 public | discover_user                        | table    | aqolirupsmmmqz
 public | discover_user_id_seq                 | sequence | aqolirupsmmmqz
 public | django_admin_log                     | table    | aqolirupsmmmqz
 public | django_admin_log_id_seq              | sequence | aqolirupsmmmqz
 public | django_content_type                  | table    | aqolirupsmmmqz
 public | django_content_type_id_seq           | sequence | aqolirupsmmmqz
 public | django_session                       | table    | aqolirupsmmmqz
 public | django_site                          | table    | aqolirupsmmmqz
 public | django_site_id_seq                   | sequence | aqolirupsmmmqz
 public | hello_greeting                       | table    | aqolirupsmmmqz
 public | hello_greeting_id_seq                | sequence | aqolirupsmmmqz
 public | polls_choice                         | table    | aqolirupsmmmqz
 public | polls_choice_id_seq                  | sequence | aqolirupsmmmqz
 public | polls_question                       | table    | aqolirupsmmmqz
 public | polls_question_id_seq                | sequence | aqolirupsmmmqz
 [other tables, but no more polls tables]
 public | south_migrationhistory               | table    | aqolirupsmmmqz
 public | south_migrationhistory_id_seq        | sequence | aqolirupsmmmqz
(45 rows)

app01::YELLOW=> \q

现在为了更新并创建polls_survey，我按照建议运行migrate命令...但是，psql表没有更新。有什么建议吗？以下是命令的完整响应：

```
（app01）MoriartyMacBookAir13：getstartapp macuser $ sudo python manage.py migrate polls 运行民意调查的迁移： - 没什么可迁移的。 - 加载民意调查的初始数据。从0个夹具中安装0个对象（app01）MoriartyMacBookAir13：getstartapp macuser $ sudo python manage.py syncdb 同步... 创建表格...... 安装自定义SQL ... 安装索引...... 从0个灯具安装了0个对象

Synced:
 > django.contrib.admin
 > django.contrib.auth
 > django.contrib.contenttypes
 > django.contrib.sessions
 > django.contrib.messages
 > django.contrib.staticfiles
 > storages
 > evernote
 > discover
 > hello
 > south
 > django.contrib.sites
 > djrill
 > allauth.socialaccount.providers.linkedin

Not synced (use migrations):
 - polls
 - allauth
 - allauth.account
 - allauth.socialaccount
 - allauth.socialaccount.providers.facebook
(use ./manage.py migrate to migrate these)
(app01)MoriartyMacBookAir13:getstartapp macuser$ sudo python manage.py migrate polls
Running migrations for polls:
- Nothing to migrate.
 - Loading initial data for polls.
Installed 0 object(s) from 0 fixture(s)
(app01)MoriartyMacBookAir13:getstartapp macuser$ 

(app01)MoriartyMacBookAir13:getstartapp macuser$ sudo python manage.py convert_to_south polls
This application is already managed by South.
(app01)MoriartyMacBookAir13:getstartapp macuser$ sudo python manage.py migrate polls
Running migrations for polls:
- Nothing to migrate.
 - Loading initial data for polls.
Installed 0 object(s) from 0 fixture(s)
(app01)MoriartyMacBookAir13:getstartapp macuser$ sudo python manage.py schemamigration polls --auto
Nothing seems to have changed.
(app01)MoriartyMacBookAir13:getstartapp macuser$

```

也就是说，polls_survey仍然不存在于psql表中，但syncdb和migrate没有效果......所以psql没有反映python描述的数据模型......

有什么建议我在这里做错了吗？

如果有用：settings.py文件中包含我的heroku psql登录详细信息，因此为什么我能够成功运行heroku pg：psql命令

Answer 1

我认为在更改模型和添加模型之前，您必须运行 schemamigration --initial 。运行 schemamigration --initial 后，更改模型并添加新模型。然后运行schemamigration --auto，然后运行命令。它应相应地更改您的数据库。

步骤

运行python manage.py schemamigration民意调查 - 初始（在更改模型之前）
更改models.py
运行python manage.py schemamigration polls --auto
运行python manage.py migrate polls

南迁移没有更新psql表（django）

models.py

终端

1 个答案: