Relational Algebra Exercises
Pubs Database Schema
author(author id, f irst name,last name)
author pub(author id, pub id,author position)
book(book id, book title, month, year, editor)
pub(pub id, title, book id)
•author id in author pub is a foreign key referencing author
•pub id in author pub is a foreign key referencing pub
•book id in pub is a foreign key referencing book
•editor in book is a foreign key referencing author(author id)
•Primary keys are underlined
Pubs Database State
r(author)
author id first name last name
1 John McCarthy
2 Dennis Ritchie
3 Ken Thompson
4 Claude Shannon
5 Alan Turing
6 Alonzo Church
7 Perry White
8 Moshe Vardi
9 Roy Batty
r(author pub)
author id pub id author position
1 1 1
2 2 1
3 2 2
4 3 1
5 4 1
5 5 1
6 6 1
r(book)
book id book title month year editor
1 CACM April 1960 8
2 CACM July 1974 8
3 BST July 1948 2
4 LMS November 1936 7
5 Mind October 1950 NULL
6 AMS Month 1941 NULL
7 AAAI July 2012 9
8 NIPS July 2012 9
r(pub)
pub id title book id
1 LISP 1
2 Unix 2
3 Info Theory 3
4 Turing Machines 4
5 Turing Test 5
6 Lambda Calculus 6
Figure 1: Relational Database Schema
