GATE | Sudo GATE 2020 Mock III (24 January 2019) | Question 21

Consider the following table T1:

P is the primary key, Q is the foreign key referencing P in table with on-delete cascade. In order to delete record (8, 5) from table, numbers of additional record that need to be deleted from table is ______.
(A) 3
(B) 2
(C) 5
(D) 4


Answer: (C)

Explanation: Whenever we delete (8, 5) from table, then, additional records that need to be deleted from table are (5, 8), (9, 8), (3, 8), (7, 3), and (6, 9).

So, answer is 5.

Option (C) is correct.

Quiz of this Question