GATE CS 2015 Set 1 — Question 32

MCQ+1 / -0.33EasyPrimary & Secondary IndexesIndexing & File OrganizationDatabasesDense vs Sparse Indexes

Databases → Indexing & File Organization → Dense vs Sparse Indexes

Last updated 5 September 2026

Question

A file is organized so that the ordering of data records is the same as or close to the ordering of data entries in some index. Then that index is called

Correct answer (C) Clustered Solution A clustered index is an index where the physical order of rows in the data file matches the order of the entries in the index. Since a file can be physically sorted in only one order, there can be at most one clustered index per file. If the data records are not ordered according to the index key, the index is called an unclustered (or secondary) index. Turn this into a strength. Explore AI-powered practice and doubt support with Success Tracker.

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Correct answer (C) Clustered Solution A clustered index is an index where the physical order of rows in the data file matches the order of the entries in the index. Since a file can be physically sorted in only one order, there can be at most one clustered index per file. If the data records are not ordered according to the index key, the index is called an unclustered (or secondary) index.

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