I am a newbie in django.I am using eclipse for development and My OS is widows 7.I have an app named Mystudent.I am using sqlite3 database.My issue is that When I type python manage.py migrate Mystudent it shows a Fatal error that following sql query is failed.It says table table Mystudent__student already exists.When I deleted and run this command,it still show this error.I have attached the screen shot.My powershell screen shot is .My admin page is :
You can try to "fake" the migrate. If the table already exists, you can tell south to update to the latest migration by forcing it using the fake option. See south django migrate
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I changed the name of several models on Django. Successfully ran makemigrations and migrate. I can interact with the SQLite directly as admin or through requests on localhost.
before changing the tables I had deployed to Heroku and it was working. when I changed the model names and pushed to Heroku (after successfully running on localhost) I get issues. When I login as admin to the site (on Heroku) I can interact with tables like User and Token, but not with the newly updated models. as soon as I click on them I get bellow error. when I click on add to these models, the columns appear but as soon as I hit save I get below error as well.
ProgrammingError at /admin/app_name/model_name/
relation "app_name_model_name" does not exist
LINE 1: SELECT COUNT(*) AS "__count" FROM "app_name_model_name"
I kept the Debug=True to see what's going on otherwise I get "500 Internal Server Error". I have added heroku's site as "ALLOWED_HOSTS".
When I was trying to make the migrations work, I had delete the files on the migration folder. not sure if there is a similar process on Heroku or if I'm missing something else?
By the way I have ran the migration commands using "heroku run bash" too. also, some of the models only had name changes, some had field updates too, but all of them throw the same error on Heroku.
I removed the app entirely from Heroku and recreated. it's working now.
I'm new django web framework. I have a models.py file where i given information about my entity fields, i ran the manage.py migrate command table generated i have alter the table manually without touch the models.py later I have run the python manage.py inspectdb > myapp/models.py in controller level using os.system models.py updated then i have tried models.objects.all() I'm unable to get the newly added field, I have called the view By using ajax call , after page refresh only new field name coming.
can you help how to get all field names with in the ajax response only with out page refresh. It would be grateful if you can help me
Note: I have checked in view level only with out page refresh first time only new column not came after page refresh it came
Thanks in advance...
I'm looking for cache in django
Before migrating, you need to create migrations.
If your DB is correctly configured, here you are (python3/python depending on version that you are using):
First: python3 manage.py makemigrations
Second: python3 manage.py migrate
makemigrations creates SQL queries, and migrate runs it. You can read more here: Django 1.8 - what's the difference between migrate and makemigrations?
I am running a GIS application while getting this error. I have attached error snapshot . Can Someone guide where is error ? If need to see code . Let me know which file you need.
Especially the first line of your exception value pretty much says it all.
Column users.parent_id does not exist
The application is trying to access parent.id from the users table from your database, which obviously does not exist. With other words, your database is not sync with the model structure in the source code. Probably all you have to do, is to run the migrations to add all the missing structures or changes to your database.
If you've developed some of the database structures yourself, you have to run the makemigrations command to build the new migration set for your database.
./manage.py makemigrations
If you have created new migration files or if you have installed and integrated modules into your app, you have to apply the migrations to your database.
./manage.py migrations
I have a django 1.8 app working with a db.
I'm trying to change the schema of a table using the built-in migration.
Here are the steps I did:
In my dev invironment, I grabbed the app source and ran
python manage.py sycdb
then I ran
python manage.py loaddata ~/my_data.json
then I modified modes.py. Added a field and renamed a field...all from the same table 'TABLE1' which had no data.
then
python manage.py makemigrations myapp
python manage.py migrate
Error: django.db.utils.OperationalError: table "myapp_someother_table" already exists
then ran
python manage.py migrate --fake-initial
worked!
but when I browsed to the admin page for TABLE1, I get this error:
OperationalError: no such column: myapp_table1.my_new_field_id
I checked the db and yes, there is no such column.
How can I procceed from here? I prefer to fix this via django.
If I fix it straight in the db, then the migration goes out of sync.
Migrations do not automagically see that you have made changes. Migrations detect changes by comparing the current model with the historical model saved in the migration files.
In this case, you didn't have any historical models, since you didn't have any migrations. Django was not able to detect any changes in your models, even though they were different from your database.
The correct way to make changes to your model is to first run manage.py makemigration <my_app>, and then make the changes to your model, followed by another manage.py makemigrations.
You might not be able to do it via pure django and keep your data. I don't have personal experience with south but there are a lot of mentions if this tool. Just in case if nothing else works for you...
Here is what I did to make things work, but there must be a better way so please add more answers/comments...
I deleted the sqlite db and the migration folder
I made the desired changes to model.py
ran syncdb
ran loaddata to load the json data dump that I had saved previously.
just started the dev server
I'm using sqlite3 and pycharm to learn more about django, and googled to find that south is recommended to make it easier to modify models after they have been created.
I'm trying to follow the advice on http://south.aeracode.org/docs/tutorial/part1.html#starting-off.
The most success I've had so far is to create a simple model and run syncdb before adding south to installed_apps. That way the intial tables are created and I get a chance to create a super user. (Django admin seems to fret if there are no users).
Then I add south to installed_apps, and run django_manage.py schemamigration bookmarks --initial
It seems to work fine. A new directory is created called migrations with a couple of files in it in my app folder and an encouraging message.
"Created 0001_initial.py. You can now apply this migration with: ./manage.py migrate bookmarks"
The next step - django_manage.py" migrate bookmarks generates the following error message
django.db.utils.DatabaseError: no such table: south_migrationhistory.
I thought that table would be created in the first schememigration step. What am I missing? Can anyone help?
Marg
South uses a table if its own to keep track of which migrations have been applied. Before you can apply any migrations, this must have been created, using python ./manage.py syncdb.
As well as for setting up south, you will find syncdb sometimes necessary for non-south apps in your project, such as the very common django.contrib.auth.
Note that as a convenience, you can run both in one go like this
python ./manage.py syncdb --migrate
My latest (unsuccessful) effort was the following
Create application – synch db – superuser created
Test run –admin screen shows basic tables
Add south, and syncdb from command line with manage.py syncdb – south_migrationhistory table created. Add basic vanilla model
Tried various combinations of manage.py syncdb –manage, and
schemamigration from Pycharm (if run from within pycharm a
migrations directory is created within the app
– if run from the command line the directory does not seem to be
created.)
Django admin screen shows table – but if I try to edit
the table it says that it doesn’t exist
Check database structure
using SQLite browser - table for newly created model doesn’t exist
I’m starting to think that the whole thing is not worth the time wasting hassle – maybe I’m better off just modifying the tables in SQLite browser
Answer in the similar question:
Run syncdb to add the Django and South tables to the database.