Unable to migrate, django.db.migrations.exceptions.MigrationSchemaMissing

Question

I have no valuable data in my database and was unable to migrate, as you can see here:

ResetDjango postgresql database? flush does not work

I tried to reset the database using:

Delete migration files

Enter psql command prompt. Connect to database. drop schema public cascade; create schema public;

Step 2 unfortunately seemed to have removed my user role and rights so I went back to the psql command promt and recreated those.

Now I have tried to migrate again, and it still doesn't work. What might be wrong now?

vagrant@vagrant-ubuntu-trusty-64:/vagrant/grader$ python3 manage.py makemigrations
Migrations for 'core':
  0001_initial.py:
    - Create model Student
vagrant@vagrant-ubuntu-trusty-64:/vagrant/grader$ python3 manage.py migrate     Traceback (most recent call last):
  File "/usr/local/lib/python3.4/dist-packages/django/db/backends/utils.py", line 62, in execute
    return self.cursor.execute(sql)
psycopg2.ProgrammingError: no schema has been selected to create in


The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.4/dist-packages/django/db/migrations/recorder.py", line 57, in ensure_schema
    editor.create_model(self.Migration)
  File "/usr/local/lib/python3.4/dist-packages/django/db/backends/base/schema.py", line 284, in create_model
    self.execute(sql, params or None)
  File "/usr/local/lib/python3.4/dist-packages/django/db/backends/base/schema.py", line 110, in execute
    cursor.execute(sql, params)
  File "/usr/local/lib/python3.4/dist-packages/django/db/backends/utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/usr/local/lib/python3.4/dist-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/usr/local/lib/python3.4/dist-packages/django/db/utils.py", line 95, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/usr/local/lib/python3.4/dist-packages/django/utils/six.py", line 685, in reraise
    raise value.with_traceback(tb)
  File "/usr/local/lib/python3.4/dist-packages/django/db/backends/utils.py", line 62, in execute
    return self.cursor.execute(sql)
django.db.utils.ProgrammingError: no schema has been selected to create in


During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python3.4/dist-packages/django/core/management/__init__.py", line 350, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python3.4/dist-packages/django/core/management/__init__.py", line 342, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python3.4/dist-packages/django/core/management/base.py", line 348, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/usr/local/lib/python3.4/dist-packages/django/core/management/base.py", line 399, in execute
    output = self.handle(*args, **options)
  File "/usr/local/lib/python3.4/dist-packages/django/core/management/commands/migrate.py", line 89, in handle
    executor = MigrationExecutor(connection, self.migration_progress_callback)
  File "/usr/local/lib/python3.4/dist-packages/django/db/migrations/executor.py", line 20, in __init__
    self.loader = MigrationLoader(self.connection)
  File "/usr/local/lib/python3.4/dist-packages/django/db/migrations/loader.py", line 49, in __init__
    self.build_graph()
  File "/usr/local/lib/python3.4/dist-packages/django/db/migrations/loader.py", line 176, in build_graph
    self.applied_migrations = recorder.applied_migrations()
  File "/usr/local/lib/python3.4/dist-packages/django/db/migrations/recorder.py", line 65, in applied_migrations
    self.ensure_schema()
  File "/usr/local/lib/python3.4/dist-packages/django/db/migrations/recorder.py", line 59, in ensure_schema
    raise MigrationSchemaMissing("Unable to create the django_migrations table (%s)" % exc)
django.db.migrations.exceptions.MigrationSchemaMissing: Unable to create the django_migrations table (no schema has been selected to create in
)

you tried migrate single app? like python manage.py migrate "your_app" ? — Ivan Semochkin, Jan 03 '16 at 11:04
I had not tried it before you suggested it. But I tried it just now and I get the same error output. My project only has one app so far. — user1283776, Jan 03 '16 at 11:05
have a look at this question http://dba.stackexchange.com/questions/106057/error-no-schema-has-been-selected-to-create-in — mic4ael, Jan 03 '16 at 11:08
so, if you create new db, maybe you change something in db settings? like user and db name. You need change it in settings too — Ivan Semochkin, Jan 03 '16 at 11:09
I don't believe I have created a new db or user. The db and user still axisted after running drop schema public cascade; create schema public; — user1283776, Jan 03 '16 at 11:13
@mic4ael: grant usage on schema public to public; grant create on schema public to public; solved the problem — user1283776, Jan 03 '16 at 11:20
For the record I also needed to recreate the superuser I had before I droped all the tables — user1283776, Jan 03 '16 at 11:23

score 2 · Answer 1 · edited Jul 31 '19 at 07:07

2

Adding these two lines in settings.py at the top are important for mysql to connect:

from django.db.backends.mysql.base import DatabaseWrapper
DatabaseWrapper.data_types['DateTimeField']='datetime'

edited Jul 31 '19 at 07:07

RobC

22,977
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answered Jul 31 '19 at 07:04

rit shi

21
2

Unable to migrate, django.db.migrations.exceptions.MigrationSchemaMissing

1 Answers1