Match the following with respect to ER diagram: List-1 List-2 I) Boxes P)…
2018
Match the following with respect to ER diagram:
List-1 | List-2 |
I) Boxes | P) Attributes |
II) Ovals | Q) Relationships |
III) Diamonds | R) Entities |
Answer: D. I-R, II-P, III-Q — In Entity-Relationship (ER) diagrams, three standard shapes distinguish the modeling elements: rectangles (boxes) mark entities, the standalone objects being…
- A.
I-Q, II-P, III-R
- B.
I-P, II-R, III-Q
- C.
I-R, II-Q, III-P
- D.
I-R, II-P, III-Q
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Correct answer: D
In Entity-Relationship (ER) diagrams, three standard shapes distinguish the modeling elements: rectangles (boxes) mark entities, the standalone objects being modeled; ovals mark attributes, the descriptive properties of those objects; and diamonds mark relationships, the associations connecting different entities. This shape-to-concept correspondence is fixed by ER modeling convention (Chen notation) and does not vary by diagram.
I) Boxes is a rectangle, matching R) Entities.
II) Ovals is an oval, matching P) Attributes.
III) Diamonds is a diamond, matching Q) Relationships.
This also matches how the three concepts function in a schema: entities are the “nouns” of the model (for example, Student or Course), attributes are the properties describing a noun (for example, a Student's name), and relationships are the “verbs” linking two nouns (for example, a Student enrolling in a Course) — confirming boxes-entities, ovals-attributes, diamonds-relationships independently of the shape convention alone.
So the correct correspondence is I-R, II-P, III-Q.