OperationalError /管理/租赁/租赁/

Question

我有一个包含以下字段的数据库：listingName、so、property、city、place、ownerName、房间、水、便利设施、价格、摘要、phoneNumber、phone_image、电子邮件--我不想要phone_image字段，所以我从models.py中删除了它，并应用了以下命令

python manage.py makemigrations rentals
python manage.py migrate

但我得到的是错误

OperationalError at /admin/rentals/rental/
no such column: rentals_rental.phone_image

因此，我首先删除了我的数据库，然后应用了命令python manage.py迁移，但仍然得到了相同的错误，尽管我的模型没有phone_image字段。

它在本地主机上工作，但在远程不起作用。因为我已经在数字海洋中托管了我的应用程序，包括nginx和gunicorn。

admin.py

from django.contrib import admin
from rentals.models import Rental,Gallery

class InlineGallery(admin.TabularInline):
    model = Gallery
    fk_name = 'rental'

class RentalAdmin(admin.ModelAdmin):
    inlines = [
        InlineGallery,
    ]
admin.site.register(Rental,RentalAdmin)
admin.site.register(Gallery)

models.py

ownerName = models.CharField(_("Owner's Name"),max_length=255, blank=True,null=True,
    help_text=_("Owner's Full Name"))
email = models.CharField(max_length=120,blank=True,null=True)
phoneNumber = models.PositiveIntegerField(blank=False,null=True,
    help_text=_("Phone number of contact person"))
listingName =  models.CharField(_("Lisitng Name"), max_length=255, blank=False,null=True,
    help_text=_("Title of the rental space"))
slug = models.SlugField(unique=True,blank=True,null=True)
summary = models.TextField(max_length=500, blank=True,null=True,help_text=_("Description of the rental space"))
property = models.CharField(_("Property type"),max_length=10,null=True)
room = models.PositiveIntegerField(_("No of Rooms"), blank=False, null=True,
    help_text=_("Number of bedrooms available"))
price = models.PositiveIntegerField(blank=False,null=True,
    help_text=_("Rental price of the space per month"))
city =  models.CharField(_("City"), max_length=255, blank=False,null=True,
    help_text=_("City of the rental space"))
place =  models.CharField(_("Place"), max_length=255, blank=False,null=True,
    help_text=_("Place of the rental space"))
water = models.CharField(_("water facilities"),max_length=50,null=True,
    help_text=_("Is there water facility?"))
amenities = models.CharField(_("amenities"),max_length=100,blank=True,null=True)
phone_image = models.CharField(blank=True, help_text='image form of the phone number', max_length=2048, null=True)
is_published = models.BooleanField(default=True)
created_on = models.DateTimeField(auto_now_add=True)
modified_on = models.DateTimeField(auto_now_add=True)


def __str__(self):
    return self.listingName

我在迁移文件夹中有两个迁移文件

0001_initial.py

# -*- coding: utf-8 -*-
# Generated by Django 1.9.1 on 2016-03-30 14:23
from __future__ import unicode_literals

from django.db import migrations, models
import django.db.models.deletion


class Migration(migrations.Migration):

initial = True

dependencies = [
]

operations = [
    migrations.CreateModel(
        name='Gallery',
        fields=[
            ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
            ('image', models.ImageField(blank=True, null=True, upload_to='upload/')),
        ],
        options={
            'verbose_name_plural': 'Galleries',
            'verbose_name': 'Gallery',
        },
    ),
    migrations.CreateModel(
        name='Rental',
        fields=[
            ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
            ('ownerName', models.CharField(blank=True, help_text="Owner's Full Name", max_length=255, null=True, verbose_name="Owner's Name")),
            ('email', models.CharField(blank=True, max_length=120, null=True)),
            ('phoneNumber', models.PositiveIntegerField(help_text='Phone number of contact person', null=True)),
            ('listingName', models.CharField(help_text='Title of the rental space', max_length=255, null=True, verbose_name='Lisitng Name')),
            ('slug', models.SlugField(blank=True, null=True, unique=True)),
            ('summary', models.TextField(blank=True, help_text='Description of the rental space', max_length=500, null=True)),
            ('property', models.CharField(max_length=10, null=True, verbose_name='Property type')),
            ('room', models.PositiveIntegerField(help_text='Number of bedrooms available', null=True, verbose_name='No of Rooms')),
            ('price', models.PositiveIntegerField(help_text='Rental price of the space per month', null=True)),
            ('city', models.CharField(help_text='City of the rental space', max_length=255, null=True, verbose_name='City')),
            ('place', models.CharField(help_text='Place of the rental space', max_length=255, null=True, verbose_name='Place')),
            ('water', models.CharField(help_text='Is there water facility?', max_length=50, null=True, verbose_name='water facilities')),
            ('amenities', models.CharField(blank=True, max_length=100, null=True, verbose_name='amenities')),
            ('phone_image', models.CharField(blank=True, help_text='image form of the phone number', max_length=2048, null=True)),
            ('is_published', models.BooleanField(default=True)),
            ('created_on', models.DateTimeField(auto_now_add=True)),
            ('modified_on', models.DateTimeField(auto_now_add=True)),
        ],
        options={
            'verbose_name_plural': 'Rents',
            'verbose_name': 'Rent',
        },
    ),
    migrations.AddField(
        model_name='gallery',
        name='rental',
        field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, related_name='gallery', to='rentals.Rental', verbose_name='Rental'),
    ),
]

0002_remove_rental_phone_image.py

# -*- coding: utf-8 -*-
# Generated by Django 1.9.1 on 2016-04-20 02:01
from __future__ import unicode_literals

from django.db import migrations


class Migration(migrations.Migration):

dependencies = [
    ('rentals', '0001_initial'),
]

operations = [
    migrations.RemoveField(
        model_name='rental',
        name='phone_image',
    ),
]

我怎样才能克服这个问题？我需要提供更多的信息吗？

谢谢

Answer 1

正如您在上面的答案中所说的，该字段被手动从数据库中删除，因此迁移尝试删除数据库中不再存在的字段。

通常，您不应该直接删除db中的字段，而是使用迁移。由于字段已经消失，您现在只能伪造迁移来告诉django已经进行了更改：

manage.py migrate rentals 0002 --fake

确保您是在迁移0001，否则这将是伪造的。

为了确保，您可以先运行以下命令：

manage.py migrate rentals 0001

Answer 2

这种类型的错误意味着，表phone_image中没有任何名为rental的列。因此，第二次迁移试图删除表rental中不存在的列。不知何故，您从表中删除了该列，django迁移系统没有注意到它。

作为修复，尝试以下选项之一：

1)删除0002_remove_rental_phone_image.py，在0001_initial.py中删除以下一行：('phone_image', models.CharField(blank=True, help_text='image form of the phone number'....))，并尝试应用迁移(如果它说：table rental is already exist，尝试将其从数据库中删除)；

2)删除所有迁移文件，并重新创建数据库、进行迁移并应用它们。

Answer 3

编写models.py代码时，运行命令

python manage.py makemigrations rentals

在此命令之后，您将看到0001_any_name.py，然后再次输入命令

python manage.py sqlmigrate rentals 0001    //0001 is prefix of above result

它将创建符合models.py的数据库，然后您可以迁移

python manage.pt migrate

因此，当您第一次创建数据库时，这个过程会第一次运行，但是在任何数据库列中都会出现问题，那么这个过程重复again.your问题就会解决。