(Simplifying:) I am creating a module that is a book catalog.

In SQL Server I have 3 tables to store this book catalog.
If every book has just 1 author I could suffice with just 1 table. But there are books that have multiple authors.
The 3 tables in SQL Server look like this.

The first table (BookDetails) has the following fields:
BookID                    (int)
YearOfPublishing (int)
Title                          (nvarchar)

The second table (Authors) has the following fields:
AuthorID      (int)
FirstName  (nvarchar)
LastName  (nvarchar)

The third table links the first 2 tables and has the fields:
ID             (int)
ArticleID  (int)
AuthorID  (int)

In DotNetNuke I created a BookInfo class with arrays of string as data types for the FirstName and LastName properties.
This to be able to store multiple authors for 1 book.
So the BookInfo class has the following properties:
YearOfPublishing as Integer
Title                   as String
FirstName()     as String
LastName()     as String

How do I tie this all up within the IHydratable Fill method?
Can it be done or should I use another approach?

Help is much appreciated.

Thank you Robert.

(Given your first solution:)

At what point in time would I fill the collection of Authors? I guess the (implementation of the) Fill method of the IHydratable interface doesn't lend itself for it, or does it?

Would not using the IHydratable interface slow things down or doesn't that apply to the solution you suggest?

Thanks again Robert.

Ok, that's clear.

Don't I introduce the same problem at the objAuthors / AuthorsController side? This because an author can write multiple books, just like a book can be written by multiple authors. Within "objAuthors.getAuthorsByBookID" I would have to call "CBO.FillCollection" that uses (if I'm not mistaken) the IHydratable.Fill method.