ISRO-2018
February 13, 2024ISRO-2018
February 13, 2024ISRO-2018
| Question 15 |
In E-R model, Y is the dominant entity and X is a subordinate entity
| If X is deleted, then Y is also deleted | |
| If Y is deleted, then X is also deleted | |
| If Y is deleted, then X is not deleted | |
| None of the above |
Question 15 Explanation:
→ It is the best example of referential integrity. In referential integrity, we are using a foreign key.
→ If we want to delete any entity in the dominant entity(Like primary key of a table) then subordinate entity(derived attribute) also deleted.
Note: If we want to delete any subordinate entity in entity then the dominant entity is not going to delete.
→ If we want to delete any entity in the dominant entity(Like primary key of a table) then subordinate entity(derived attribute) also deleted.
Note: If we want to delete any subordinate entity in entity then the dominant entity is not going to delete.
Correct Answer: B
Question 15 Explanation:
→ It is the best example of referential integrity. In referential integrity, we are using a foreign key.
→ If we want to delete any entity in the dominant entity(Like primary key of a table) then subordinate entity(derived attribute) also deleted.
Note: If we want to delete any subordinate entity in entity then the dominant entity is not going to delete.
→ If we want to delete any entity in the dominant entity(Like primary key of a table) then subordinate entity(derived attribute) also deleted.
Note: If we want to delete any subordinate entity in entity then the dominant entity is not going to delete.