Django 3.1: OperationalError - No Such Column/Table

Question

I've been solving this problem for the entire day. My code in my models.py is the following:

from django.db import models
from django.contrib.auth.models import User
from users.models import TeacherProfile, StudentProfile

class Course(models.Model):
    name = models.CharField(max_length=100)
    desc = models.TextField()
    short_code = models.CharField(max_length=5)
    teacher = models.ForeignKey(TeacherProfile, null=True, on_delete=models.SET_NULL)
    students = models.ManyToManyField(StudentProfile)

    def __str__(self):
        return self.name

class Partition(models.Model):
    name = models.CharField(max_length=20)
    chunk = models.FloatField()
    result = models.FloatField(blank=True)
    course = models.ForeignKey(Course, on_delete=models.CASCADE)
    
    def __str__(self):
        return self.name
    
class Activity(models.Model):
    title = models.CharField(max_length=100)
    content = models.TextField()
    file = models.FileField(blank=True)
    course = models.ForeignKey(Course, on_delete=models.CASCADE)
    parent = models.ForeignKey(Partition, on_delete=models.CASCADE)

    def __str__(self):
        return self.title
    
class Grade(models.Model):
    grade = models.FloatField()
    remarks = models.CharField(max_length=200, blank=True)
    activity = models.ForeignKey(Activity, on_delete=models.CASCADE)
    student = models.ForeignKey(StudentProfile, on_delete=models.CASCADE)

I've ran the following commands:

python manage.py makemigrations
python manage.py migrate

I even written the following command as per my research to other StackOverFlow questions related to this:

python manage.py migrate --run-syncdb

Only the Course table worked. The Activity and the Grade table received OperationalError - No Such Column and the Partition Table got an OperationalError - No Such Table.

Activity

OperationalError at /admin/course/activity/
no such column: course_activity.parent_id
Request Method: GET
Request URL:    http://127.0.0.1:8000/admin/course/activity/
Django Version: 3.1
Exception Type: OperationalError
Exception Value:    
no such column: course_activity.parent_id
Exception Location: C:\Users\hp\AppData\Local\Programs\Python\Python38-32\lib\site-packages\django\db\backends\sqlite3\base.py, line 413, in execute
Python Executable:  C:\Users\hp\AppData\Local\Programs\Python\Python38-32\python.exe
Python Version: 3.8.5
Python Path:    
['C:\\Users\\hp\\Desktop\\TechKnow\\YowBro',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\python38.zip',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\DLLs',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\lib',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\lib\\site-packages']
Server time:    Fri, 21 Aug 2020 09:47:26 +0000

Grade

OperationalError at /admin/course/grade/
no such column: course_grade.remarks
Request Method: GET
Request URL:    http://127.0.0.1:8000/admin/course/grade/
Django Version: 3.1
Exception Type: OperationalError
Exception Value:    
no such column: course_grade.remarks
Exception Location: C:\Users\hp\AppData\Local\Programs\Python\Python38-32\lib\site-packages\django\db\backends\sqlite3\base.py, line 413, in execute
Python Executable:  C:\Users\hp\AppData\Local\Programs\Python\Python38-32\python.exe
Python Version: 3.8.5
Python Path:    
['C:\\Users\\hp\\Desktop\\TechKnow\\YowBro',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\python38.zip',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\DLLs',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\lib',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\lib\\site-packages']
Server time:    Fri, 21 Aug 2020 09:47:28 +0000

Partition

OperationalError at /admin/course/partition/
no such table: course_partition
Request Method: GET
Request URL:    http://127.0.0.1:8000/admin/course/partition/
Django Version: 3.1
Exception Type: OperationalError
Exception Value:    
no such table: course_partition
Exception Location: C:\Users\hp\AppData\Local\Programs\Python\Python38-32\lib\site-packages\django\db\backends\sqlite3\base.py, line 413, in execute
Python Executable:  C:\Users\hp\AppData\Local\Programs\Python\Python38-32\python.exe
Python Version: 3.8.5
Python Path:    
['C:\\Users\\hp\\Desktop\\TechKnow\\YowBro',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\python38.zip',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\DLLs',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\lib',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32',
 'C:\\Users\\hp\\AppData\\Local\\Programs\\Python\\Python38-32\\lib\\site-packages']
Server time:    Fri, 21 Aug 2020 09:47:29 +0000

What did I do wrong?

UPDATE: I've tried putting default values to the tables. Sadly, it didn't work. Help please.

UPDATE #2: I ran python manage.py sqlmigrate course 0001. Contrary to the error it shows in the actual site, the returned SQL commands are shown below (I highlighted the SQL command for creating the table Partition for emphasis):

ASSUMPTION: Maybe the error is in the migration command. I manually deleted the tables from my DB Browser for SQLite. Then, I tried running the makemigrations and the migrations command. Though it migrates a SQL code, it doesn't create anything at all. How can we fix this?

I SOLVED THE PROBLEM! Check my answer below.

Answer 1

I FIXED THE PROBLEM.

Thanks to kerasbaz, I checked my database configuration in my Django settings. I thought that I should comment the configuration out for the SQLite and insert the PostgreSQL.

So what I first did is to create a new database through my pgAdmin. Now, you need to have pgAdmin and psycopg2 installed (pip install psycopg2). Next, I edited my database settings in my project's settings.

Here's a sample from the Django documentation:

 DATABASES = {
     'default': {
            'ENGINE': 'django.db.backends.postgresql',
            'NAME': 'mydatabase',
            'USER': 'mydatabaseuser',
            'PASSWORD': 'mypassword',
            'HOST': '127.0.0.1',
            'PORT': '5432',
       }
}

Finally, I ran makemigrations and migrate commands. Voila! I solved the problem I've been solving for five hours.

Answer 2

You can try to put related name in your models eg

class Activity(models.Model):
   title = models.CharField(max_length=100)
   content = models.TextField()
   file = models.FileField(blank=True)
   course = models.ForeignKey(Course,related_name='course_id' on_delete=models.CASCADE)
   parent = models.ForeignKey(Partition,related_name='parent_id' on_delete=models.CASCADE)

   def __str__(self):
      return self.title