Q1:

Construct an E-R diagram for the modeling of a database that contains information on academic institutions and their researchers. The following should be stored: for each researcher: ID, name, and date of birth. For each institution: name, location, and year. For each School: names such as School of Law, School of Business, School of Computer Science, etc. Each school belongs to exactly one institution. Each researcher belongs to only one school. For each researcher, information on the highest degree (BSc, MSc or PhD), and at what school. For each researcher, information about the research projects (title, start date, and end date). Information about co-authorships, i.e., which researchers have co-authered a paper including the title of the paper.

Identify the primary key of each entity, weak entities if any, one-to-one or many-to-many.etc, and include any assumptions you make.

Q2:

Consider the following E-R diagram, which models an online bookstore.

List the entity sets and their primary keys.

Q3:

In relational algebra: is the set difference commutative or not and Why?

Q4:

What is the difference between multivalued and composite attribute? Explain with Example.

NOTE: PLEASE SOLVE ALL THE QUESTION AT ONE TIME BECAUSE I PONLY HAVE 20 POST PER-MONTH AND WRITE DOWN ALL OG THE BY COMPUTRE BECAUSE IT IS HARD TO UNDERSTAND THE HAND WRITING

author address URL written by book title year price number contains number stocks publisher address phone URL ublished by shopping basket basket id warehouse address phone customer name address phone basket of