Discography and Library ERD

First Scenario - Discography

A store aims to build a database with relevant information on the disks sells.

For each disk, wish to register in the database code identification, title, number of copies sold, recording date and the group / interpreter.

Want also to include the songs that each disc includes. On each song, wish to register the title that identifies the music and the first author. The same music may appear in distinct records.

Second Scenario Library

The aim is to develop a database to store information of a library. Such database should contain at least information regarding:

• all titles in the library including each of the ISBN (which is a code assigned to international level and that uniquely identifies a book), the name, or the authors, the publisher, book descriptors, its classification;
• The locations (eg the number of the shelf) where it must meet the various books (or copies) of each of the titles;
• Relevant information about publishers (such as name, phone, address, fax, etc.);
• Readers of the library, each of which with a reader number. The library intends to have any more available information about readers, such as name, address, etc .;
• The library aims, of course, have available information about the readers who have ordered and delivered books.

NOTE: The descriptors of the books are "keywords" that provide indications about topics coveres by the books. To uniformize, the descriptos are not free, but they are choosen by a list of possible descriptos, all of them identified by a code.