Symfony2 / Doctrine mapped superclass in the middle of class table inheritance

From the Docs:

A mapped superclass is an abstract or concrete class that provides persistent entity state and mapping information for its subclasses, but which is not itself an entity. Typically, the purpose of such a mapped superclass is to define state and mapping information that is common to multiple entity classes.

That said, how can you associate one entity with one that is not?

More from the docs:

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 assocations 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.

Source: http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/inheritance-mapping.html

Update

Because your MappedSuperClass extends BaseEntity it also inherits the BaseEntity's associations, as if it were its own. So you effectively DO have a OneToMany on a MappedSuperClass.

To get around it, well, you'd need to modify/extend doctrine to work the way you want.

As far as native functionality goes you have two options:

Class Table InheritanceYou Common class and the resulting DB representation would have the common fields and child classes will now only have the fields specific to themselves. Unfortunately this may be a misrepresentation of your data if you are simply trying to group common fields for the sake of grouping them.

Make Common an EntityIt appears that all a Mapped Super Class is is an Entity that isn't represented in the DB. So, make common a Entity instead. The downside is that you'll end up with a DB table, but you could just delete that.

I recommend that you take a second look at your data and ensure that you are only grouping fields if they are common in both name and purpose. For example, a ComputerBox, a ShoeBox, a Man, and a Woman may all have the "height" property but in that case I wouldn't suggest have a Common class with a "height" property that they all inherit from. Instead, I would have a Box with fields common to ComputerBox and ShoeBox and I'd have a Person with fields common to Man and Woman. In that situation Class Table Inheritance or single table if you prefer would work perfectly.

If your data follows that example go with Single Table or Class Table Inheritance. If not, I might advise not grouping the fields.