A library has a collection of items that they loan out to members. They refer to these items as holdings (as these are the items held). For each holding, they must keep track of its estimated value and the date it was originally acquired by the library. Items can be books, audio books, DVDs, or software. For books, we need to know the publisher. Audio books, the label. DVDs, the studio. And for software, the developer. 1. Draw an ER diagram that includes all of the necessary information in a single entity.
2. Draw an EER diagram version using supertypes and subtypes. Include subtype discriminators. Indicate whether there should be subtype overlap or disjoint. Indicate whether there is full or partial specialization. Add Assumptions to the side of your diagram to justify your design choices.
3. Add an entity for Library_Patron (we need to know at least their name and email address), and create an entity to keep track of when holdings are checked out and returned (and by whom).
4. Duplicate the EER diagram you made and expanded, but this time show the reverse of your choices for disjoint/overlap and partial/full-specialization. Add Assumptions to the side of your diagram to justify your design choices.
ER diagram should be made on paper or software anything works.