Question $2.$

Consider the following relations:

Relation R$1$

Relation R$4$

Relation R$2$

Relation R$5$

Relation R$3$

Primary Keys :

Relation R$1$: A$,$B

Relation R$2$: D

Relation R$3$: $M,N,O$

Relation R$4$: $J,K$

Relation R$5$: $S$

The following foreign key constraints are given for relations $R1,R2,R3,R4$ and $R5$ :

$R3(MN)$ references $R1(AB)$

$R3(O)$ references $R2(D)$

$R1(C)$ references $R5(S)$

$R4(J)$ references $R5(S)$

$R4(K)$ references $R2(D)$

Assume

"CASCADE" policy for delete operations, and

"SET NULL" policy for update operations.

a$)(10\%)$ For the operations given below, indicate whether execution of the operation would violate some "primary key" or "integrity constraints". If your answer is yes, specify the constraints $($from the above list$)$ that would be violated.

i$)$ Insert tuple $(a1,b10,d20,35)$ into R$3.$

ii$)$ Insert tuple $(5500,d20,75)$ into R$4.$

b$)$ For the operations given below, indicate whether execution of the operation would violate any $$foreign key constraints$.$ If your answer is yes, specify the constraints $($from the above list$)$ that would be violated. Apply $$CASCADE$$ policy for delete operations, and apply $$SET NULL$$ policy for update operations. Update the tables after applying those policies.

$($You may either redraw the tables or mention which tuples$/$attributes are deleted$/$updated at each table. For updates rewrite the updated tuples.$)$ Make the changes on the original tables for each operation below.

i$)$ Delete tuple $($d$30,150,300)$ from R$2.$

ii$)$ Update tuple $($s$400,30,555)$ in R$5$ with values $(6000,60,66)$

iii$)$ Update tuple $($s$100,20,555)$ in R$5$ with values $(6000,60,666)$

c$)$ If all tuples in R$5$ are deleted, what tuples will R$2$ and R$3$ contain