Aug2016 cs Q12
0. Which one of the following pairs is correctly matched in the context of database design?
| List – I | List – II |
| (Database term) | (Definition) |
| I. Specialization | A. Result of taking the union of two or more disjoint (lower-level) entity sets to produce a higher-level entity set. |
| II. Generalization | B. Express the number of entities to which another entity can be associated via a relationship set. |
| III. Aggregation | C. Result of taking a subset of a higher-level entity set to form a lower-level entity set. |
| IV. Mapping cardinalities | D. An abstraction in which relationship sets (along with their associated entity sets) are treated as higher-level entity sets, and can participate in relationships. |
Codes:
| I | II | III | IV | |
| (1) | D | A | B | C |
| (2) | D | C | B | A |
| (3) | C | D | A | B |
| (4) | C | A | D | B |
- Option : D
- Explanation :
- Result of taking a subset of a higher-level entity set to form a lower-level entity set is Specialization
- Result of taking the union of two or more disjoint(lower-level) entity sets to produce a higher-level entity set is Generalization
- An abstraction in which relationship sets (along with their associated entity sets) are treated as higher-level entity sets, and can participate in relationships.Aggregation
- Express the number of entities to which another entity can be associated via a relationship set Mapping cardinalities
So, option (D) is correct.
