Python 3.10.4
Django 4.0.5
PostgreSQL 14
When I start "python manage.py makemigrations" i got the file "0001_initial.py" but all Fields, except autofields, are missing.
models.py
from django.db import models
# Create your models here.
class Username(models.Model):
#id = models.AutoField(primary_key=True)
username: models.CharField(max_length=100)
class Carrier(models.Model):
#id = models.AutoField(primary_key=True)
carriername: models.CharField(max_length=100)
desc: models.TextField()
0001_initial.py
# Generated by Django 4.0.5 on 2022-06-29 13:18
from django.db import migrations, models
class Migration(migrations.Migration):
initial = True
dependencies = [
]
operations = [
migrations.CreateModel(
name='Carrier',
fields=[
('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
],
),
migrations.CreateModel(
name='Username',
fields=[
('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
],
),
]
First, you must know that Django By default adds the id field to the models ...
Try to Delete the migration file and
you must use the = not the :
so it will be like this
class Username(models.Model):
username=models.CharField(max_length=100)
class Carrier(models.Model):
carriername = models.CharField(max_length=100)
desc = models.TextField()
rerun manage.py makemigrations and it Should work
Related
models.py
class Country(models.Model):
name = models.CharField(max_length=50, validators=[validate_name, ])
class Meta:
managed = False
db_table = 'countries'
def __str__(self):
return self.name
0001_initial.py
class Migration(migrations.Migration):
initial = True
dependencies = [
]
operations = [
migrations.CreateModel(
name='Country',
fields=[
('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('name', models.CharField(max_length=50, validators=[countries.validators.validate_name])),
],
options={
'db_table': 'countries',
'managed': False,
},
),
]
sql
(venv) michael#michael:~/Documents/PyCharmProjects/db/db$ python manage.py sqlmigrate countries 0001_initial
BEGIN;
--
-- Create model Country
--
-- (no-op)
COMMIT;
Could you tell me whether this sql reflects the model or not? If not, how can it happen? And will it produce in the database?
There is no sql to apply to the db because of managed = False.
That is, running migrate does not change the db.
I created a dummy project just to test the new field JSONField of Django but the column doesn't not appear to be created (I am using Postgresql).
class Author(models.Model):
name = models.CharField(max_length=50)
description = models.TextField()
slug = models.SlugField()
details = models.JSONField()
class Meta:
verbose_name = "Author"
def __str__(self):
return self.name
If i go to the database, the column is not created -- screenshot
When i go to the admin view page of the table Author i get the following error -- screenshot
The error in the admin panel is understandable: you cannot view a column that does not exist. Do you guys have the same error? I can't find this error with JSONField anywhere.
Thanks
Note: This is my first post.
EDIT I create all the fields in the same time. Migration file:
# Generated by Django 3.1.3 on 2020-11-20 10:35
from django.db import migrations, models
class Migration(migrations.Migration):
initial = True
dependencies = [
]
operations = [
migrations.CreateModel(
name='Author',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('name', models.CharField(max_length=50)),
('description', models.TextField()),
('slug', models.SlugField()),
('details', models.JSONField()),
],
options={
'verbose_name': 'Author',
},
),
]
Migrated with sucess:
Migrations for 'blog':
blog/migrations/0001_initial.py
- Create model Author
check that you migration was applied to the right database
I'm just wondering what the correct syntax is for calling $ python manage.py migrate app_name --database db_name with the management.call_command() function at runtime.
So far, I have the following:
from django.core import management
from django.core.management.commands import migrate
# Migrate the core.contrib.dynamics if needed to the pre-specified database:
management.call_command(migrate.Command(), 'dynamics', '--database {}'.format(DB_NAME))
However, I get the following error at runtime when calling the above:
Cannot find a migration matching '--database default_node' from app 'dynamics'.
I'm 99% sure I'm probably calling the -- args incorrectly? Can anyone point me in the right direction with this?
The migrations for the dynamics app are as follows:
# Generated by Django 3.0.8 on 2020-07-02 14:28
from django.db import migrations, models
import django.db.models.deletion
class Migration(migrations.Migration):
initial = True
dependencies = [
]
operations = [
migrations.CreateModel(
name='ModelSchema',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('name', models.CharField(max_length=32, unique=True)),
('_modified', models.DateTimeField(auto_now=True)),
],
),
migrations.CreateModel(
name='FieldSchema',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('name', models.CharField(max_length=63)),
('data_type', models.CharField(choices=[('character', 'character'), ('text', 'text'), ('integer', 'integer'), ('float', 'float'), ('boolean', 'boolean'), ('date', 'date')], editable=False, max_length=16)),
('null', models.BooleanField(default=False)),
('unique', models.BooleanField(default=False)),
('max_length', models.PositiveIntegerField(null=True)),
('model_schema', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='fields', to='dynamics.ModelSchema')),
],
options={
'unique_together': {('name', 'model_schema')},
},
),
]
Considering you already ran the migrations, you can simply use
management.call_command('migrate', app_label='dynamics', database='dbname')
THIS IS MY MODEL FILE
from django.db import models
class Donor(models.Model):
Donor_name = models.CharField(max_length=150),
Donor_status = models.IntegerField(),
Donor_city = models.CharField(max_length=50),
Donor_group = models.CharField(max_length=10),
Donor_phone = models.CharField(max_length=12),
Donor_mail = models.EmailField(max_length=50)
THIS IS MY MIGRATION
Generated by Django 2.0.2 on 2018-03-30 09:19
from django.db import migrations, models
class Migration(migrations.Migration):
initial = True
dependencies = [
]
operations = [
migrations.CreateModel(
name='Donor',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
],
)
Why are other fields ignored ?
using Django version 2 with MySQL.
The commas at the end of the lines cause Python to treat them as tuples. Remove them.
class Donor(models.Model):
Donor_name = models.CharField(max_length=150)
Donor_status = models.IntegerField()
Donor_city = models.CharField(max_length=50)
Donor_group = models.CharField(max_length=10)
Donor_phone = models.CharField(max_length=12)
Donor_mail = models.EmailField(max_length=50)
Once you have made this change, you can run makemigrations again and Django should include your new fields. If you haven't run the migration that creates the modlel yet, you could remove the migration file before doing this. You can use python manage.py showmigrations to check whether the migration has already been run.
Note that in Django, the recommendation is to use lowercase_with_underscores for your field names, e.g. donor_name and donor_status.
'authorid' is a foreign key to the Django 'User' model. After running 'makemigrations' and 'migrate' I can not see this field in the sqlite shell.
Here are my models,
class TopicModel(models.Model):
topic = models.CharField(max_length = 100)
topicAuthor = models.CharField(max_length = 100)
authorid = models.ForeignKey(User, related_name = 'id_of_author')
views = models.PositiveIntegerField(default = 0)
def __str__(self):
return self.topic
class PostModel(models.Model):
post = HTMLField(blank = True, max_length = 1000)
pub_date = models.DateTimeField('date published')
author = models.CharField(max_length = 30)
topicid = models.ForeignKey(TopicModel, related_name = 'posts')
def __str__(self):
return self.post
As you can see postmodel also has a foreign key to the topicmodel and there is no problem with this foreign key.
After migration the migrate file 0001_initial.py looks like this,
from __future__ import unicode_literals
from django.conf import settings
from django.db import migrations, models
import django.db.models.deletion
import tinymce.models
class Migration(migrations.Migration):
initial = True
dependencies = [
migrations.swappable_dependency(settings.AUTH_USER_MODEL),
]
operations = [
migrations.CreateModel(
name='PostModel',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('post', tinymce.models.HTMLField(blank=True, max_length=1000)),
('pub_date', models.DateTimeField(verbose_name='date published')),
('author', models.CharField(max_length=30)),
],
),
migrations.CreateModel(
name='TopicModel',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('topic', models.CharField(max_length=100)),
('topicAuthor', models.CharField(max_length=100)),
('views', models.PositiveIntegerField(default=0)),
('authorid', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='id_of_author', to=settings.AUTH_USER_MODEL)),
],
),
migrations.AddField(
model_name='postmodel',
name='topicid',
field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='posts', to='crudapp.TopicModel'),
),
]
In the sqlite shell the postmodel shows the field with the foreign key, which is topicid_id
sqlite> PRAGMA table_info(crudapp_postmodel);
0|id|integer|1||1
1|pub_date|datetime|1||0
2|author|varchar(30)|1||0
3|topicid_id|integer|1||0
4|post|text|1||0
But when I do the same with the topicmodel, the field with the foreign key doesn't exist, so there is no authorid field.
sqlite> PRAGMA table_info(crudapp_topicmodel);
0|id|integer|1||1
1|topic|varchar(100)|1||0
2|topicAuthor|varchar(100)|1||0
3|views|integer unsigned|1||0
Solution: As suggested by Alasdair I deleted the sqlitedb file and changed the fields from from topicid and authorid to topic and author.
Your current migration should create the foreign keys. My guess is that you updated the migration file after you had already created the crudapp_topicmodel table in the database.
If you don't have any important data yet, the easiest fix is to delete your sqlite file and rerun ./manage.py migrate.