How is class inheritance supposed to work?

[Sendu Bala]

In Studio 2.1, I created a class X with 2 properties. Then I created Y as a subclass of X since it was to have the same 2 properties. Then I created Z as a subclass of X since it was to have the same 2 properties, plus another. But adding the extra property to Z also added the property to X and Y. Likewise, with class A being a subclass of X, deleting a property of A also deletes it from X.

Is this a bug in Studio, or is this expected behaviour of classes and subclasses? If a subclass can't have different properties compared to it's parent, what is the intended use of inheritance?

[MV-dev1]

I thought it worked exactly like you expected it to work.

Maybe I haven't tried more than 2 levels.  I did just write a post here about it combining a single INDEX over all children -- maybe this was a newly introduced issue?

I tried to use OrientDB for something a 5 months ago but eventually gave up and went back to MSSQL however I think the concepts here are the greatest things I've seen since C++ added OOP features to C and that was 1989!

[alessand...@gmail.com]

Hi,

I created a class X with 2 properties.

I created a class Y that inherit from X.

I created a class Z that inherit from X and I added a new property.

Adding the new property to Z, it isn't added to class X and class Y but only at the class Z.

I created a class A that inherit from X.

If I try to delete the property1(inherit from X) from class A, I get this error:

com.orientechnologies.orient.core.exception.OSchemaException: Property 'property1' not found in class A'

Being A a subclass of X you can't delete a property inherited because A would not be anymore a subclass of X .

Regards,

Alessandro

[Sendu Bala]

Woops, looks like I got confused; it was indexes of properties that were not independent.

Are you supposed to create abstract classes with unindexed properties, and then create the index for those properties in each subclass?

[alessand...@gmail.com]

Hi,

I created an abstract class X with one property and an index on that property.

I create a class Y that inherit from X, it inherit the property and the index.

I deleted the index inherited from class Y and the index was deleted also from class X.

I thought that would not allow to delete the index from class X and Y.

Regards,

Alessandro