I accidentally used the mapped superclass inheritance type on an abstract entity with a recursive relation (one-to-many with itself) when I should have used the class table inheritance type. After 'Export to ORM' Doctrine wouldn't create the database. After some searching, I fount the following in the Doctrine documentation:
A mapped superclass cannot be an entity, it is not query-able and persistent relationships defined by a mapped superclass must be unidirectional (with an owning side only). This means that One-To-Many associations are not possible on a mapped superclass at all. Furthermore Many-To-Many associations are only possible if the mapped superclass is only used in exactly one entity at the moment. For further support of inheritance, the single or joined table inheritance features have to be used.
So Skipper allowed me to create that relation when doctrine doesn't permit this.
