How many records will the cartesian product operation produce?
Question:
5. Assume relations R and S with tuples 10 and 5 respectively. How many records will be there in the result of the operation R X S (i.e., R cartesian product S)?
(a) 10 records
(b) 5 records
(c) 50 records
(d) 15 records
Answer:
(c) 50
R X S will include every tuple of R with every tuple of S and produce a redundant number of records. Refer the example given below;
R
|
|||
A
|
B
|
C
|
|
Tuple 1
|
a1
|
b1
|
c1
|
Tuple 2
|
a2
|
b2
|
c2
|
Tuple 3
|
a3
|
b3
|
c3
|
S
|
||
B
|
D
|
|
Tuple 1
|
b1
|
d1
|
Tuple 2
|
b2
|
d3
|
R
X S
|
|||||
A
|
R.B
|
C
|
S.B
|
D
|
|
Tuple 1
|
a1
|
b1
|
c1
|
b1
|
d1
|
Tuple 2
|
a1
|
b1
|
c1
|
b2
|
d3
|
Tuple 3
|
a2
|
b2
|
c2
|
b1
|
d1
|
Tuple 4
|
a2
|
b2
|
c2
|
b2
|
d3
|
Tuple 5
|
a3
|
b3
|
c3
|
b1
|
d1
|
Tuple 6
|
a3
|
b3
|
c3
|
b2
|
d3
|
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