TAILIEUCHUNG - Lecture Database system concepts (6/e): Chapter 10 - Silberschatz, Korth, Sudarshan

Chapter 10 - Storage and file structure. In this chapter, we probe below the higher levels as we describe various methods for implementing the data models and languages presented in preceding chapters. We start with characteristics of the underlying storage media, such as disk and tape systems. We then define various data structures that allow fast access to data. | Chapter 10: Storage and File Structure Database System Concepts, 6th Ed. ©Silberschatz, Korth and Sudarshan See for conditions on re-use Chapter 10: Storage and File Structure Overview of Physical Storage Media Magnetic Disks RAID Tertiary Storage Storage Access File Organization Organization of Records in Files Data-Dictionary Storage Database System Concepts - 6th Edition ©Silberschatz, Korth and Sudarshan Classification of Physical Storage Media Speed with which data can be accessed Cost per unit of data Reliability data loss on power failure or system crash physical failure of the storage device Can differentiate storage into: volatile storage: loses contents when power is switched off non-volatile storage: Contents persist even when power is switched off. Includes secondary and tertiary storage, as well as batterbacked up main-memory. Database System Concepts - 6th Edition ©Silberschatz, Korth and Sudarshan Physical Storage Media Cache – fastest and most costly form of storage; volatile; managed by the computer system hardware. Main memory: fast access (10s to 100s of nanoseconds; 1 nanosecond = 10–9 seconds) generally too small (or too expensive) to store the entire database capacities of up to a few Gigabytes widely used currently Capacities have gone up and per-byte costs have decreased steadily and rapidly (roughly factor of 2 every 2 to 3 years) Volatile — contents of main memory are usually lost if a power failure or system crash occurs. Database System Concepts - 6th Edition ©Silberschatz, Korth and Sudarshan Physical Storage Media (Cont.) Flash memory Data survives power failure Data can be written at a location only once, but location can be erased and written to again Can support only a limited number (10K – 1M) of write/erase cycles. Erasing of memory has to be done to an entire bank of memory Reads are roughly .

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• Database system
• Lecture Database system
• Relational databases
• Database design
• File structure
• Magnetic disks
• Tertiary storage
• Database system concepts
• Lecture Database system concepts
• Database systems
• Database languages
• Database system architectures
• Relational database design
• Database system architecture
• File based approach
• Data management systems framework
• Recovery system
• Lecture Database systems
• Database architecture
• Database approach
• Database design process
• Query optimization
• Transaction state
• Concurrency control
• Data analysis
• Information retrieval
• Parallel databases
• Distributed databases
• Advanced application development
• Advanced data types
• Advanced transaction processing
• Relational model
• Basic query structure
• Dynamic SQL
• Tuple relational calculus
• Entity relationship model
• Application design
• Object­ based databases