Table updated in Drupal and by External Code

I am converting a Joomla site to Drupal. The Joomla site uses the application builder tool Fabrik which can connect to an external MySQL database. Drupal Content Types and Entities with bundles place custom fields in separate tables rather than a single table as per the Joomla site. However if I create an Entity in Drupal and put all the fields in the entity rather than in separate bundles, would this be a safe route to sharing a table between Drupal and another application ( both applications should be able to update the table ) – or is this likely to result in problems ? If this is not a good idea, what is the recommended approach to allow editable data to be displayed in Drupal Views, yet shared with another application. Any thoughts much appreciated. Thanks.

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