django.db.utils.ProgrammingError：关系“bot_trade”不存在

Question

我试图在cookeicutter上建立一个网站，我创建了一个名为“bots”的新应用程序，并在模型中添加了一个名为Trade的类，其中列出了两个参数，“标题”和“单位”。迁移并运行服务器后，当我打开管理面板并单击面板中的“+添加”按钮创建交易（请参见图片）。 Django的网页返回此错误：

django.db.utils.ProgrammingError: relation "bot_trade" does not exist 
LINE 1: ...."id", "bots_unit"."sell", "bots_unit"."buy" FROM "bots_unit... 

产生额外的信息： PostgreSQL的

pic of admin panel

Models.py

from django.db import models 
from datetime import date 
#from django.contrib.auth.models import AbstractUser 
#from .models import User 
from django.urls import reverse 
from django.urls import reverse_lazy 
from django.conf import settings 
import uuid 


class Unit(models.Model): 

TRADE_UNIT = (
    ('ETH', 'Ethereum'), 
    ('BTC', 'Bitcoin'), 
    ('LTC', 'Litecoin'), 
    ('IOT', 'IOTA'), 
    ('OMG', 'OmiseGo'), 
    ('BCH', 'BitcoinCash'), 

) 

sell = models.CharField(max_length=3, choices=TRADE_UNIT, blank=True, default='ETH', help_text='Currency to Sell') 
buy = models.CharField(max_length=3, choices=TRADE_UNIT, blank=True, default='BTC', help_text='Currency to Buy') 

def get_absolute_url(self): 
    """ 
    Returns the url to access a particular author instance. 
    """ 
    return reverse('unit-detail', args=[str(self.id)]) 

def __str__(self): 
    """ 
    String for representing the Model object. 
    """ 
    return '%s, %s' % (self.sell, self.buy) 

class Meta: 
    db_table = 'bots_unit' 
    ordering = ['sell','buy'] 


class Trade(models.Model): 
title = models.CharField(max_length=200) 
unit = models.ForeignKey('Unit', on_delete=models.SET_NULL, null=True) 


def __str__(self): 
    """ 
    String for representing the Model object. 
    """ 
    return self.title 

def get_absolute_url(self): 
    """ 
    Returns the url to access a particular book instance. 
    """ 
    return reverse('trade-detail', args=[str(self.id)]) 

class Meta: 
    db_table = 'bots_trade' 


class TradeInstance(models.Model): 
""" 
Model representing a specific copy of a book (i.e. that can be borrowed from the library). 
""" 
id = models.UUIDField(primary_key=True, default=uuid.uuid4, help_text="Unique ID for this particular trade across whole database") 
trade = models.ForeignKey('Trade', on_delete=models.SET_NULL, null=True) 
amount = models.CharField(max_length=200) 
price = models.CharField(max_length=200) 
imprint = models.CharField(max_length=200) 
time_initiated = models.DateTimeField(null=True, blank=True) 
#initiator = models.ForeignKey(AbstractUser, 
on_delete=models.SET_NULL, null=True, blank=True) 

position_status = (
    ('L', 'Long'), 
    ('S', 'Short'), 
) 

position = models.CharField(max_length=1, choices=position_status, blank=True, default='L', help_text='Order Type') 

class Meta: 
    ordering = ["position"] 


def __str__(self): 
    """ 
    String for representing the Model object 
    """ 
    return '%s (%s)' % (self.id,self.trade.title) 

Admin.py

泊坞窗内运行我的Django的

from django.contrib import admin 
from .models import Trade, TradeInstance, Unit 



# Define the admin class 
@admin.register(Trade) 
class TradeAdmin(admin.ModelAdmin): 
    pass 


@admin.register(Unit) 
class UnitAdmin(admin.ModelAdmin): 
    pass 

UPDATE1： 我删除了迁移里面的内容的文件夹了几次，但是这是目前什么是“0001.initial.py”内部运行“makemigrations”和“迁移”后：

# -*- coding: utf-8 -*- 
# Generated by Django 1.10.8 on 2017-10-12 17:55 
from __future__ import unicode_literals 

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


class Migration(migrations.Migration): 

    initial = True 

    dependencies = [ 
    ] 

    operations = [ 
     migrations.CreateModel(
      name='Trade', 
      fields=[ 
       ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')), 
       ('title', models.CharField(max_length=200)), 
      ], 
     ), 
     migrations.CreateModel(
      name='TradeInstance', 
      fields=[ 
       ('id', models.UUIDField(default=uuid.uuid4, help_text='Unique ID for this particular trade across whole database', primary_key=True, serialize=False)), 
       ('amount', models.CharField(max_length=200)), 
       ('price', models.CharField(max_length=200)), 
       ('imprint', models.CharField(max_length=200)), 
       ('time_initiated', models.DateTimeField(blank=True, null=True)), 
       ('position', models.CharField(blank=True, choices=[('L', 'Long'), ('S', 'Short')], default='L', help_text='Order Type', max_length=1)), 
       ('trade', models.ForeignKey(null=True, on_delete=django.db.models.deletion.SET_NULL, to='bots.Trade')), 
      ], 
      options={ 
       'ordering': ['position'], 
      }, 
     ), 
     migrations.CreateModel(
      name='Unit', 
      fields=[ 
       ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')), 
       ('sell', models.CharField(blank=True, choices=[('ETH', 'Ethereum'), ('BTC', 'Bitcoin'), ('LTC', 'Litecoin'), ('IOT', 'IOTA'), ('OMG', 'OmiseGo'), ('BCH', 'BitcoinCash')], default='ETH', help_text='Currency to Sell', max_length=3)), 
       ('buy', models.CharField(blank=True, choices=[('ETH', 'Ethereum'), ('BTC', 'Bitcoin'), ('LTC', 'Litecoin'), ('IOT', 'IOTA'), ('OMG', 'OmiseGo'), ('BCH', 'BitcoinCash')], default='BTC', help_text='Currency to Buy', max_length=3)), 
      ], 
      options={ 
       'ordering': ['sell', 'buy'], 
      }, 
     ), 
     migrations.AddField(
      model_name='trade', 
      name='unit', 
      field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, to='bots.Unit'), 
     ), 
    ] 

当我运行 'showmigrations'：

dominic@dom-Inspiron-7559:~/Desktop/Projects/vickibot/vicki$ docker-compose -focal.yml run django python manage.py showmigrations 
Postgres is up - continuing... 
account 
[X] 0001_initial 
[X] 0002_email_max_length 
admin 
[X] 0001_initial 
[X] 0002_logentry_remove_auto_add 
auth 
[X] 0001_initial 
[X] 0002_alter_permission_name_max_length 
[X] 0003_alter_user_email_max_length 
[X] 0004_alter_user_username_opts 
[X] 0005_alter_user_last_login_null 
[X] 0006_require_contenttypes_0002 
[X] 0007_alter_validators_add_error_messages 
[X] 0008_alter_user_username_max_length 
bots 
[X] 0001_initial 
contenttypes 
[X] 0001_initial 
[X] 0002_remove_content_type_name 
sessions 
[X] 0001_initial 
sites 
[X] 0001_initial 
[X] 0002_alter_domain_unique 
[X] 0003_set_site_domain_and_name 
socialaccount 
[X] 0001_initial 
[X] 0002_token_max_lengths 
[X] 0003_extra_data_default_dict 
users 
[X] 0001_initial 

UPDATE2：

'manage.py迁移--fake机器人零'输出：

dominic@dom-Inspiron-7559:~/Desktop/Projects/vickibot/vicki$ **docker-compose -f local.yml run django python manage.py migrate --fake bots zero** 
Postgres is up - continuing... 
Operations to perform: 
    Unapply all migrations: bots 
Running migrations: 
    Rendering model states... DONE 
    Unapplying bots.0001_initial... FAKED 

'manage.py迁移机器人' 输出：

dominic@dom-Inspiron-7559:~/Desktop/Projects/vickibot/vicki$ docker-compose -f local.yml run django python manage.py migrate bots 
Postgres is up - continuing... 
Operations to perform: 
    Apply all migrations: bots 
Running migrations: 
    Applying bots.0001_initial... OK 

Answer 1

你可能还没有创建任何迁移您bot应用程序。您需要指定应用程序名称，创建初始迁移：

./manage.py makemigrations bot 

然后运行迁移到运行迁移，并创建缺少的表：

./manage migrate 

当您运行showmigrations，你可以看到的Django认为它已经为您的bots应用程序应用了初始迁移。这可能是因为你为该应用运行了--fake。

bots 
[X] 0001_initial 

你可以告诉Django，以纪念迁移为未应用，然后重新运行迁移：

manage.py migrate --fake bots zero 
manage.py migrate bots 

这应该工作，只要不从bots应用程序中创建表呢。如果只创建了一些表格，那么修改数据库将会更加棘手。