Steps to reproduce the issue

Create custom table class with assets (property $asset_id is required) and try to execute parent::store(true).

Or just edit libraries/src/Table/Content.php, replace at the bottom return parent::store($updateNulls); with return parent::store(true); to emulate the real case, next try to save an article.

Expected result

Save without errors.

Actual result

See error.

System information (as much as possible)

Joomla 3.9.22

Additional comments

The issue is that JTable::store() uses $updateNulls param for saving asset table instance as well and it will fail due to NULL alias property which is missed in #__assets table.