This is a novice question from a newbie regarding mapping ERD generalization hierarchies (GH) schema using table inheritance in Postgresql.
There are cases where the specialization tables in a generalization hierarchy allow overlapping to occur. To illustrate this point with an example, a GH for employee could have a generalized table employee and overlapping specialized tables Manager and Programmer. An employee that was both a manager and a programmer would have a record inserted into each specialized table.
My question is, will the generalized table have duplicate records for this employee or will uniqueness be maintained? Or are rules and triggers required to maintain normalization of the generalized table.
Regards,
Richard B.