Chapter 15, Problem 10PE

Explanation of Solution

a.

Semi-join operation:

• Consider the two given relation “r” and “s”. To perform semi-join operation between the two relations using sorting:
• Initially, sort the relation “r” on the join attributes in predicate θ.
• Then sort relation “s” on the join attributes in predicate θ.
• Like merge algorithm, scan the relation “r” and “s”.
• Check whether the join attributes of current records of relation “r” and “s” is match.
  • Add records of relation “r” to the result...

Explanation of Solution

b.

Anti-semi-join operation:

• To perform anti-semi-join operation between the two relation using sorting;
• Initially, sort relation “r” on the join attributes in predicate θ.
• Next, sort relation “s” on the join attributes in predicate θ.
• Like merge algorithm, scan the relation “r” and “s”.
• Check if no record of relation “s” gratifies the join predicate for the corresponding record in “r”...