Modern disk drives store more sectors on the outer tracks than the inner tracks. Since the rotation speed is constant, the sequential data transfer rate is also higher on the outer tracks. The seek time and rotational delay are unchanged. Considering this information, explain good strategies for placing files with the following kinds of access patterns: 1. Frequent, random accesses to a small file (e.g., catalog relations). 2. Sequential scans of a large file (e.g., selection from a relation with no index). 3. Random accesses to a large file via an index (e.g., selection from a relation via the index).

Modern disk drives store more sectors on the outer tracks than the inner tracks. Since the rotation speed is constant, the sequential data transfer rate is also higher on the outer tracks. The seek time and rotational delay are unchanged. Considering this information, explain good strategies for placing files with the following kinds of access patterns: 1. Frequent, random accesses to a small file (e.g., catalog relations). 2. Sequential scans of a large file (e.g., selection from a relation with no index). 3. Random accesses to a large file via an index (e.g., selection from a relation via the index).

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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