Re: why hierarchy?

> > > Basic Requirements: A business has many staff members (with full names and a start date), some of whom are direct supervisors over other staff members. The business has many clients (with full names), and each client is registered on a specific date by a specific staff member.
> >
> > Ok, please specify specific data for the above.
>
> The data values are not part of the initial specifications.

With dbd, user doesn't design a schema. When you have finished designing the schema, please post it. We can then start adding some initial data that might look like the below or not. Write a few queries. Then someone can suggest unanticipated data, ie store the asset(s) that each person/company owns some possibly shared. Adapting each solution to the new data will allow us to evaluate or extrapolate each data representation methodology's resiliency/generality.

Company IBM has 6 employees. There boss/employee hierarchy as follows:   John Smith (hired 7/4/45)

     Mary Lee (hired 5/3/65)
        Suzie Merk  (hired 8/8/88)
     Bob Lewis (hired 3/8/08)
        Rick Branson (hired 8/9/48, 1/3/67 and 5/13/88)

              Jack (hired 3/5/89) has two bosses: John and Suzie.

IBM has 5 clients (2 companies, 3 individuals) registered on date(s) indicated by employee(s)

    Dell                   reg by Mary on 1/1/01
    Microsoft Inc         reg by Suzie and Rick on 3/5/02 and 5/8/54
    Warren Buffet         reg by Bob on 5/8/02
    George W. Bush III  reg by Mary, Suze, Bob, Rick  on 5/8/06
    J Carter                   ref by John on 3/4/92