1 Reply Latest reply on Jul 12, 2019 1:29 PM by Philip Stoyanov-Oracle

    How to forward engineer a relational model in case of inheritance of attributes

    0d02dab9-d09a-4552-ad41-596899499adb

      Hello community,

       

      i hope that someone can help me with this one.

       

      I'm using SQL Developer Data Modeler Version 19.1.0.081.

       

      i've developed a simple logical model (ERM) with 4 entities (customer (E1), privat_customer (E2), business_customer (E3), account (E4)) and different attributes.

       

      E1: customer:

      • - customer_id (PK)
      • - surename
      • - lastname
      • - address

       

      E2: private_customer: (Super Type = customer) E2 inherits from E1

      • - birthday
      • - interessts

       

      E3: business_customer (Super Type = customer) E3 inherits from E1

      • - company_size
      • - lei
      • - legal_form

       

      E4: account

      • - account_id (PK)
      • - customer_id (FK)
      • - product_name
      • - category
      • - price
      • - reference

       

      Now the situation:

      I want to engineer three different relational models (R1, R2, R3) from the above logical model

      • R1 contains all entities except of attribute "address" from E1
      • R2 contains all entities except of attribute "lei" from E3
      • R3 contains all entities except of attribute "reference" from E4

      Therefore i choosed within the attribute settings "Engineer to" and deselect the related relational model, as it is discribed within the help file.

       

      My observation:

      • R3 has been engineered without the attribute reference from E4 which seems to be correct for me
      • R1 and R2 are engineered including the above attributes and after the engineering process, the "engineer to" settings within the attribute has been reset to the default value automatically (all ceckboxes are checked) . This can't be right and must depend of the iheritence or something else.

       

      Is this behavior correct?

      If yes, is there a different way to exclude attributes from relational model, that must be included in the logical model?

       

      Thank you very much for your support.

       

      Kind regdas

      Karl