ORA-01451: column to be modified to NULL cannot be modified to NULL

[matwrob]

Hi Team,
I'm working on a Django project that's supposed to run on Oracle 19c database.
I'm developing locally in containers using Oracle XE latest image.
When trying to apply migrations (no custom models, only Django & django-auditlog):
>> docker compose run --rm app sh -c "python manage.py migrate"

Oracle rejects the following migration: 0015_alter_logentry_changes

`DB is available
Operations to perform:
Apply all migrations: admin, auditlog, auth, contenttypes, knox, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
Applying auth.0001_initial... OK
Applying admin.0001_initial... OK
Applying admin.0002_logentry_remove_auto_add... OK
Applying admin.0003_logentry_add_action_flag_choices... OK
Applying auditlog.0001_initial... OK
Applying auditlog.0002_auto_support_long_primary_keys... OK
Applying auditlog.0003_logentry_remote_addr... OK
Applying auditlog.0004_logentry_detailed_object_repr... OK
Applying auditlog.0005_logentry_additional_data_verbose_name... OK
Applying auditlog.0006_object_pk_index... OK
Applying auditlog.0007_object_pk_type... OK
Applying auditlog.0008_action_index... OK
Applying auditlog.0009_alter_logentry_additional_data... OK
Applying auditlog.0010_alter_logentry_timestamp... OK
Applying auditlog.0011_logentry_serialized_data... OK
Applying auditlog.0012_add_logentry_action_access... OK
Applying auditlog.0013_alter_logentry_timestamp... OK
Applying auditlog.0014_logentry_cid... OK
Applying auditlog.0015_alter_logentry_changes...Traceback (most recent call last):
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/utils.py", line 89, in _execute
return self.cursor.execute(sql, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/oracle/base.py", line 557, in execute
return self.cursor.execute(query, self._param_generator(params))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
cx_Oracle.DatabaseError: ORA-01451: column to be modified to NULL cannot be modified to NULL

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

Traceback (most recent call last):
File "/app/manage.py", line 24, in
main()
File "/app/manage.py", line 20, in main
execute_from_command_line(sys.argv)
File "/opt/venv/lib64/python3.11/site-packages/django/core/management/init.py", line 442, in execute_from_command_line
utility.execute()
File "/opt/venv/lib64/python3.11/site-packages/django/core/management/init.py", line 436, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/opt/venv/lib64/python3.11/site-packages/django/core/management/base.py", line 412, in run_from_argv
self.execute(*args, **cmd_options)
File "/opt/venv/lib64/python3.11/site-packages/django/core/management/base.py", line 458, in execute
output = self.handle(*args, **options)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/core/management/base.py", line 106, in wrapper
res = handle_func(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/core/management/commands/migrate.py", line 356, in handle
post_migrate_state = executor.migrate(
^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/migrations/executor.py", line 135, in migrate
state = self._migrate_all_forwards(
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/migrations/executor.py", line 167, in _migrate_all_forwards
state = self.apply_migration(
^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/migrations/executor.py", line 252, in apply_migration
state = migration.apply(state, schema_editor)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/migrations/migration.py", line 132, in apply
operation.database_forwards(
File "/opt/venv/lib64/python3.11/site-packages/django/db/migrations/operations/fields.py", line 235, in database_forwards
schema_editor.alter_field(from_model, from_field, to_field)
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/oracle/schema.py", line 75, in alter_field
super().alter_field(model, old_field, new_field, strict)
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/base/schema.py", line 830, in alter_field
self._alter_field(
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/base/schema.py", line 1055, in _alter_field
self.execute(
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/base/schema.py", line 201, in execute
cursor.execute(sql, params)
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/utils.py", line 102, in execute
return super().execute(sql, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/utils.py", line 67, in execute
return self._execute_with_wrappers(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/utils.py", line 80, in _execute_with_wrappers
return executor(sql, params, many, context)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/utils.py", line 84, in _execute
with self.db.wrap_database_errors:
File "/opt/venv/lib64/python3.11/site-packages/django/db/utils.py", line 91, in exit
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/utils.py", line 89, in _execute
return self.cursor.execute(sql, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/venv/lib64/python3.11/site-packages/django/db/backends/oracle/base.py", line 557, in execute
return self.cursor.execute(query, self._param_generator(params))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
django.db.utils.DatabaseError: ORA-01451: column to be modified to NULL cannot be modified to NULL`

The migration in question is the following:

-- Add field changes_text to logentry

ALTER TABLE "AUDITLOG_LOGENTRY" ADD "CHANGES_TEXT" NCLOB DEFAULT '' NULL;
ALTER TABLE "AUDITLOG_LOGENTRY" MODIFY "CHANGES_TEXT" DEFAULT NULL;

-- Alter field changes on logentry

ALTER TABLE "AUDITLOG_LOGENTRY" MODIFY "CHANGES" NULL;
ALTER TABLE "AUDITLOG_LOGENTRY" ADD CONSTRAINT "AUDITLOG__CHANGES_2C529CA8_C" CHECK ("CHANGES" IS JSON);

And the problematic statement is:
ALTER TABLE "AUDITLOG_LOGENTRY" MODIFY "CHANGES" NULL;

Is this issue known?

I understand that Oracle does not allow modifying an existing column from NOT NULL to NULL.
If the issue is well known, is there a "standard" approach to solve it?

[hramezani]

django-auditlog is not supporting oracle DB