Django Migrations: How to resolve error of charfield to datetimefield-CodePudding

What im doing is i clone my prod database to sandbox. and I'm getting error while migrate Cause of previously I made charfield to datetime field. And then datetime field to Charfield after few migrations.

So how do I solve below error:

Error :

python manage.py migrate
System check identified some issues:

WARNINGS:
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, pro_auth, service_list, sessions, token_blacklist
Running migrations:
  Applying pro_auth.0002_alter_userorder_order_booking_time...Traceback (most recent call last):
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
psycopg2.errors.InvalidDatetimeFormat: invalid input syntax for type timestamp with time zone: "2021-10-10 10.00"


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

Traceback (most recent call last):
  File "manage.py", line 22, in <module>
    main()
  File "manage.py", line 18, in main
    execute_from_command_line(sys.argv)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/core/management/__init__.py", line 419, in execute_from_command_line
    utility.execute()
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/core/management/__init__.py", line 413, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/core/management/base.py", line 354, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/core/management/base.py", line 398, in execute
    output = self.handle(*args, **options)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/core/management/base.py", line 89, in wrapped
    res = handle_func(*args, **kwargs)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/core/management/commands/migrate.py", line 244, in handle
    post_migrate_state = executor.migrate(
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/migrations/executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/migrations/executor.py", line 227, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/migrations/migration.py", line 126, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/migrations/operations/fields.py", line 244, in database_forwards
    schema_editor.alter_field(from_model, from_field, to_field)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/base/schema.py", line 608, in alter_field
    self._alter_field(model, old_field, new_field, old_type, new_type,
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/postgresql/schema.py", line 196, in _alter_field
    super()._alter_field(
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/base/schema.py", line 765, in _alter_field
    self.execute(
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/base/schema.py", line 145, in execute
    cursor.execute(sql, params)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/utils.py", line 98, in execute
    return super().execute(sql, params)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/utils.py", line 66, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/utils.py", line 75, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/utils.py", line 90, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/root/sandbox/sandbox_venv/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
django.db.utils.DataError: invalid input syntax for type timestamp with time zone: "2021-10-10 10.00"

And Here is Migration file 0002_alter_userorder_order_booking_time:

from django.db import migrations, models
import django.utils.timezone


class Migration(migrations.Migration):

    dependencies = [
        ('pro_auth', '0001_initial'),
    ]

    operations = [
        migrations.AlterField(
            model_name='userorder',
            name='order_booking_time',
            field=models.DateTimeField(default=django.utils.timezone.now),
        ),
    ]

CodePudding user response：

I think, you need fake migration.

Try this

./manange.py migrate --fake <app_name_of_userorder_is_inclueded> <last_migration_number_which_synced_current_order_booking_time>

This make skip applying alter table.

CodePudding user response：

You're not passing a valid DateTimeFormat. I think you should write

field=models.DateTimeField(default=django.utils.timezone.now()),

based on what is shown here: Django default=timezone.now() saves records using "old" time