TAILIEUCHUNG - Lecture Database system concepts (6/e): Chapter 19 - Silberschatz, Korth, Sudarshan

Chapter 19 - Distributed databases. Chapter 19 covers distributed database systems, revisiting the issues of database design, transaction management, and query evaluation and optimization, in the context of distributed databases. The chapter also covers issues of system availability during failures, heterogeneous distributed databases, cloud-based databases, and distributed directory systems. | Chapter 19: Distributed Databases Database System Concepts, 6th Ed. ©Silberschatz, Korth and Sudarshan See for conditions on re-use Chapter 19: Distributed Databases Heterogeneous and Homogeneous Databases Distributed Data Storage Distributed Transactions Commit Protocols Concurrency Control in Distributed Databases Availability Distributed Query Processing Heterogeneous Distributed Databases Directory Systems Database System Concepts - 6th Edition ©Silberschatz, Korth and Sudarshan Distributed Database System A distributed database system consists of loosely coupled sites that share no physical component Database systems that run on each site are independent of each other Transactions may access data at one or more sites Database System Concepts - 6th Edition ©Silberschatz, Korth and Sudarshan Homogeneous Distributed Databases In a homogeneous distributed database All sites have identical software Are aware of each other and agree to cooperate in processing user requests. Each site surrenders part of its autonomy in terms of right to change schemas or software Appears to user as a single system In a heterogeneous distributed database Different sites may use different schemas and software Difference in schema is a major problem for query processing Difference in software is a major problem for transaction processing Sites may not be aware of each other and may provide only limited facilities for cooperation in transaction processing Database System Concepts - 6th Edition ©Silberschatz, Korth and Sudarshan Distributed Data Storage Assume relational data model Replication System maintains multiple copies of data, stored in different sites, for faster retrieval and fault tolerance. Fragmentation Relation is partitioned into several fragments stored in distinct sites Replication and fragmentation can be combined Relation is partitioned into .

• Cơ sở dữ liệu
• Database system
• Lecture Database system
• Relational databases
• Database design
• Distributed databases
• Homogeneous databases
• 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
• 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