Perhaps I am looking at my entities as a hierarchy rather than a set of relationships; for sake of an example I have three tables:

• Authors
• Books
• Content

Where Authors writes Books and Books contain content.

The rules for these entities is as follows:

• Content cannot stand alone without association to a Book
• a Book cannot stand alone without association to an Author

See below the following partial implementation:

CREATE TABLE authors(    author_id integer,    author_name varchar,    author_age int,     PRIMARY KEY (author_id) );  CREATE TABLE books(    book_id integer,    author_id integer,    book_title varchar,    book_published date,     PRIMARY KEY (book_id, author_id),    FOREIGN KEY (author_id) REFERENCES authors(author_id) ); 

From here I believe I have created a relationship where Books relies on Authors, should it decide to exist.

Arguably some may say that Content can simply just be part of Books, but say that Content has a hefty amount of columns in association to it and that a person would prefer to keep the more general Book data separate from its Content data for simplicity purposes.

In the event of the latter, how can I write a create statement that will make Content dependent on Books?