Is referential integrity supported? Does Drupal 8 support referential integrity? Can I tell Drupal what it should do if a parent row in a content type is deleted? For example:


I could tell Drupal not to allow the deletion of a parent row if it has child rows
I could tell Drupal to delete all child rows that belong to a parent row when that parent row is deleted


By row I mean an item of a content type. For example, if the content type is Book, a row is the data about one book.
No, there's no such feature out of the box.

For D7, there is a module for that, but I haven't see a Drupal 8 version: https://www.drupal.org/project/erri.

We did build something like that ourself based on the entity_usage module, we alter the node delete form and display a warning that shows where the node is used.