ACtE08 · Chapter 8Demo2 · Set 2🏛️ Past Licensure QuestionID: fcbc2813
In Database Management Systems (DBMS), how many fundamental types of relationship cardinalities (mapping cardinality ratios) are formally recognized between entity sets?
In Database Management Systems (DBMS), how many fundamental types of relationship cardinalities (mapping cardinality ratios) are formally recognized between entity sets?
Multiple Choice Options
- A
2
- B
3
- C✓ Correct Option
4
- D
5
Detailed Technical Solution & Explanation
In relational database design and Entity-Relationship (ER) modeling, mapping cardinalities define the number of entities in one entity set that can be associated with entities in another set. Formally, there are 4 fundamental mapping cardinality ratios:
1. One-to-One (1:1)
2. One-to-Many (1:N)
3. Many-to-One (N:1)
4. Many-to-Many (M:N)
Option Analysis:
•
Option A (2): Incorrect; inadequate to describe many-to-many or asymmetric mappings.
•
Option B (3): Incorrect; ignores the directional distinction between 1:N and N:1 in directional mapping specifications.
•
Option C (4): Correct; the four universal mapping constraints in DBMS are 1:1, 1:N, N:1, and M:N.
•
Option D (5): Incorrect; beyond the standard relational cardinality model.
Reference: Demo2 · Set 2NEC Licensure Syllabus