Mini Project

 Mini Project Presentation

        As usual we started our class at 2pm at TECC Room. Today, we have a Mini Project Presentation about Relational Algebra. This Mini Project has 20% of PB which is the second biggest of all PB that we have for subject Database System. There have 5 groups that must be present in front of Madam Shamsiah while she recorded.

        Relational Algebra is a theoretical language with operations that work on one or more relations to define another relation without changing the original relation(s).  Both the operands and the results are relations. Below is the explanation of each Relational Algebra.

1. SELECT

    The selection operation works on a single relation R and defines a relation that contains only those tuples of R that satisfy the specified condition (predicate).

    Syntax:  predicate(R)

    Example:-

2. PROJECT

    The Projection operation works on a single relation R and defines a relation that contains a vertical subset of R, extracting the values of specified attributes and eliminating duplicates.

    Syntax: a1, . . . , an(R)

    Example:-

3. UNION

    The union of two relations R and S defines a relation that contains all the tuples of R, or S, or both R and S, duplicate tuples being eliminated. R and S must be union-compatible.

    Syntax: R  S

    Example:-

4. INTERSECTION

    The Intersection operation defines a relation consisting of the set of all tuples that are in both R and S. R and S must be union-compatible. 

    Syntax: R  S 

     Example:-

5. DIFFERENCE

    The set Difference operation defines a relation consisting of the tuples that are in relation R, but not in S. R and S must be union-compatible.

    Syntax: R - S

    Example:-

    After all presentation are done, we take a picture for our class and our beloved lecturer, Madam Shamsiah because it's our last class for this semester. The examination is a round the corner.