CISC437 Chapter Notes - Chapter 10.1: Blu-Ray, Database Design, Flash Memory
11 Apr 2016
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Document Summary
Several types of storage exist in computer systems. Classified by speed of data access, cost ($), and reliability. Cache: fastest, yet most costly form of storage, relatively small amount of memory, not all that significant for database design. Main memory: the storage medium used for data that are available to be operated on is main memory, although it may contain several gigabytes of data, it is generally too small to store an entire database. Flash memory: stored data is retained even if power is turned off, lower cost per byte than main memory, widely used for storing data in usb keys which can be plugged into the usb. Magnetic disk storage: primary medium for long-term online storage of data, survives power failures and system crashes, data is moved from disk to main memory, accessed and/or modified, and written back to disk. Optical storage: cd"s, dvd"s, blu-ray, data stored on disk and read by a laser.
