retagged by
2,315 views

2 Answers

6 votes
6 votes

Since candidate key not define so max tupple will be 20*10 = 200.

if R1 has candidate key P and R2 has candidate key R .

then No. of max tupple will be depend on foriegn key attribute relation so here  R⟕ R2 = 20

4 votes
4 votes

here,nothing is given about referential integrity so,we apply some case

CASE 1 (default): All values of R1(R) and R2(R) are same then 20*10=200

CSAE 2: suppose R2(R) references  R1(R) (foreign key) and all the values are same in  R2(R)  then,

             1 tuple of R1(R)  matches with 10 tuples of  R2(R) then no of combination=10

          and 19 tuples left in  R1 which also come in resultant table with NULL values for  R2 tables attributes value

          so,19 no of more tuples

         so, total =10+19=29

CASE 3: if we change RI make  R1(R) references  R2(R) then if all values R1(R)  is same 

                     then, also as in case 2, i.e. 20+9=29

CASE 4: if r be act as primary key (unique) for both the table then for EX

             R1

P Q R S
a d 1 o
b e 2 u
c f 3 g

R2

R G T U
4 k n q
5 l o r
6 m p s

R1(leftouter join)R2

P Q R S R G T U
a d 1 o n n n n
b e 2 u n n n n
e f 3 g n n n n

so,all left part of table present with null values is right part of table

so,cardinality of left table will be maxm no of tuples so, 20 will be maxm

 

edited by

Related questions

0 votes
0 votes
1 answer
1
srestha asked Dec 16, 2017
1,521 views
Consider the relation schema:Student(roll no, name course no)Enroll(roll no, course no,course name)The number of tuples in the student and enroll table is 30 and 40 respe...
3 votes
3 votes
2 answers
2
iarnav asked Dec 6, 2017
1,255 views
Say we have two relations R (a,b,c) and S (b,d,e).Now, R has 200 tuples and S has 300 tuples. What will be Minimum number of tuples when we do R ⋈ S ( ⋈ = Natural Joi...
2 votes
2 votes
1 answer
3
4 votes
4 votes
4 answers
4
kauray asked May 9, 2017
3,679 views
Suppose you are given relations r(A, B) and s(A, C). Suppose that r has 10000 tuples, and s has 5000 tuples. Suppose attribute r.A has 1001 distinct values, and s.A also ...