In a relational database management system, data spread across multiple files is logically organized as what structures?
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Atables
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Brelations
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Ctuples
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Dboth (a) and (b)
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ENone of the above
Answer
Correct Answer: both (a) and (b)
Explanation
Introduction / Context: Relational database terminology distinguishes the logical model from physical storage. Understanding the terms helps when reading documentation and communicating design decisions between engineers, DBAs, and analysts.
Given Data / Assumptions:
- We are discussing the logical organization of data in an RDBMS.
- Multiple files may exist physically, but the user sees logical structures.
- We must choose appropriate relational terms.
Concept / Approach: In relational theory, a relation is the abstract mathematical construct; in practice, DBMSs expose this as a table. Rows are tuples and columns are attributes. Therefore, saying an RDBMS organizes data as tables/relations is correct, while “tuple” refers to a row, not the whole organizational unit.
Step-by-Step Solution:
Map theory to practice: relation ↔ table, tuple ↔ row, attribute ↔ column. Identify the organizational unit that holds rows and columns: the table/relation. Choose the combined answer that names both equivalent terms.Verification / Alternative check: Textbooks and DBMS manuals commonly equate “relation (table)” while reserving “tuple” for an individual record.
Why Other Options Are Wrong:
- Only tables or only relations: each is correct but incomplete relative to theory/practice pairing.
- Tuple: a row, not the organizing container.
- None: incorrect because both tables and relations are appropriate descriptors.
Common Pitfalls: Using “file” to mean “table”; conflating physical storage files with logical tables; forgetting that a single table can span multiple physical files or partitions.
Final Answer: both (a) and (b)