Outline Centralized Database Systems Server System Architectures Parallel Systems ■ Distributed Systems Network Types Database System Concepts-7th Edition 20.2 ©Silberscha乜，Korth and Sudarshan
Database System Concepts - 7 20.2 ©Silberschatz, Korth and Sudarshan th Edition Outline ▪ Centralized Database Systems ▪ Server System Architectures ▪ Parallel Systems ▪ Distributed Systems ▪ Network Types
Centralized Database Systems Run on a single computer system ■Single-user system ·Embedded databases Multi-user systems also known as server systems. Service requests received from client systems Multi-core systems with coarse-grained parallelism Typically a few to tens of processor cores In contrast,fine-grained parallelism uses very large number of computers Database System Concepts-7th Edition 20.3 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 20.3 ©Silberschatz, Korth and Sudarshan th Edition Centralized Database Systems ▪ Run on a single computer system ▪ Single-user system • Embedded databases ▪ Multi-user systems also known as server systems. • Service requests received from client systems • Multi-core systems with coarse-grained parallelism ▪ Typically a few to tens of processor cores ▪ In contrast, fine-grained parallelism uses very large number of computers
Server System Architecture Server systems can be broadly categorized into two kinds: ·transaction servers Widely used in relational database systems,and ·data servers Parallel data servers used to implement high-performance transaction processing systems Database System Concepts-7th Edition 20.4 ©Silberscha乜，Korth and Sudarshan
Database System Concepts - 7 20.4 ©Silberschatz, Korth and Sudarshan th Edition Server System Architecture ▪ Server systems can be broadly categorized into two kinds: • transaction servers ▪ Widely used in relational database systems, and • data servers ▪ Parallel data servers used to implement high-performance transaction processing systems
Transaction Servers Also called query server systems or SQL serversystems Clients send requests to the server Transactions are executed at the server Results are shipped back to the client. Requests are specified in SQL,and communicated to the server through a remote procedure call(RPC)mechanism. Transactional RPC allows many RPC calls to form a transaction. Applications typically use ODBC/JDBC APIs to communicate with transaction servers Database System Concepts-7th Edition 20.5 ©Silberscha乜，Korth and Sudarshan
Database System Concepts - 7 20.5 ©Silberschatz, Korth and Sudarshan th Edition Transaction Servers ▪ Also called query server systems or SQL server systems • Clients send requests to the server • Transactions are executed at the server • Results are shipped back to the client. ▪ Requests are specified in SQL, and communicated to the server through a remote procedure call (RPC) mechanism. ▪ Transactional RPC allows many RPC calls to form a transaction. ▪ Applications typically use ODBC/JDBC APIs to communicate with transaction servers
Transaction System Processes(Cont.) user user user process process process ODBC JDBC server server server process process process process buffer pool monitor shared process memory query plan cache lock log buffer lock table manager process database log writer checkpoint writer process process process log disks data disks Database System Concepts-7th Edition 20.6 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 20.6 ©Silberschatz, Korth and Sudarshan th Edition Transaction System Processes (Cont.)