Consider the following relations R1 (A, B, C) and R2 (D, E, F).
|
R1 |
|
|
|
A |
B |
C |
|
1 |
5 |
3 |
|
6 |
10 |
4 |
|
5 |
4 |
3 |
|
3 |
8 |
6 |
|
1 |
5 |
6 |
|
R2 |
|
|
|
D |
E |
F |
|
1 |
5 |
3 |
|
5 |
4 |
5 |
|
1 |
5 |
4 |
|
3 |
8 |
5 |
What will be the result of the following relational algebraic expression?
\({\pi _{A,B}}\left( {{\sigma _{\left( {C = 3} \right){{\rm{V}}({{\rm{C}} = 6)}}}}\left( {R1} \right)} \right)\; - {\pi _{D,E}}\left( {{\sigma _{\left( {F = 5} \right){\rm{V}}\left( {{\rm{F}} = 3} \right)}}\left( {R2} \right)} \right)\)
1
relation with attributes (A, B) and tuples {(1,5)}
2
tuples {(5,4) and (3,8)}
3
empty relation
4
relation with attributes (A, B) and tuples {(1,5)(5,4)(3,8)}