DBSQL 12-1 Copyright © Genetic Computer School 2009 Chapter 12 Recent Concepts and Application of Databases

DBSQL 12-2 Copyright © Genetic Computer School, Singapore 2009 Chapter 12 Overview Advance Application Development Performance Tuning Performance Benchmark Standardization Advance Data Types and New Applications Temporal Data Spatial and Geographic Data Multimedia Databases Mobile and Personal Databases XML Advanced Transaction Processing Transaction Processing Monitor Transactional Workflows High Performance Transaction Systems Main-Memory Database Real-Time Transaction Systems Long Duration Transactions Transaction Management in Multi-databases

DBSQL 12-3 Copyright © Genetic Computer School, Singapore 2009 Advance Application Development Performance Tuning -- It means optimizing the performance of the database -- A database can be tuned in various level -- Hardware -- Database System parameters -- Higher level database design

DBSQL 12-4 Copyright © Genetic Computer School, Singapore 2009 Cont’ Performance Benchmark Are suites of task used to quantify the performance of software systems Commonly used performance measures  Throughput  Response time  Availability

DBSQL 12-5 Copyright © Genetic Computer School, Singapore 2009 Cont’ Standardization The complexity of contemporary database systems and the need for their interoperation require a variety standards like syntax and semantics of programming. Two common type of standardization  Anticipatory standards  Reactionary standards

DBSQL 12-6 Copyright © Genetic Computer School, Singapore 2009 Advance Data Types and New Applications Temporal Data model the states of the real world across time Example relation:

DBSQL 12-7 Copyright © Genetic Computer School, Singapore 2009 Cont’ Spatial and Geographic Data store data like points, lines, regions, volumes, and aim at supporting queries that involve the space characteristics of these data Examples  GIS (Geographical Information Systems  Multimedia Information Systems  CAD/CAM applications  Medical Information Systems

DBSQL 12-8 Copyright © Genetic Computer School, Singapore 2009 Cont’ Multimedia Databases must support multimedia data types in addition to providing facilities for traditional DBMS functions like database creation, data modelling, data retrieval, data access and organization, and data independence. The area and applications have experienced tremendous growth. Multimedia Data  refers to the simultaneous use of data in different media forms, including images, audio, video, text, and numerical data

DBSQL 12-9 Copyright © Genetic Computer School, Singapore 2009 Cont’ Mobile and Personal Databases A mobile database should be defined as the union of distributed database, disconnected database, ad hoc database and broadcast disks.

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ Architecture of Mobile Database

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ XML Extensible Markup Language (XML) is a simplified version of SGML (Standard Generalized Markup Language defined by ISO 8879) designed for Web Applications XML was developed by an XML Working Group (originally known as the SGML Editorial Review Board) formed under the auspices of the World Wide Web Consortium (W3C) in 1996

DBSQL Copyright © Genetic Computer School, Singapore 2009 Advance Transaction Processing Transaction Processing Monitor TP monitors are initially developed as multi-threaded servers to support large numbers of terminals from a single process

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ Transactional Workflows Workflows are activities that involve the coordinated execution of multiple tasks performed by different processing entities. With the growth of networks, and the existence of multiple autonomous database systems, workflows provide a convenient way of carrying out tasks that involve multiple systems

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ Examples of Workflow

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ High Performance Transaction Systems High-performance hardware and parallelism help improve the rate of transaction processing, but are insufficient to obtain high performance

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ Main Memory Databases Commercial 64-bit systems can support main memories of tens of gigabytes.  Memory resident data allows faster processing of transactions  Disk-related limitations Logging is a bottleneck when transaction rate is high Use group-commit to reduce number of output operations If the update rate for modified buffer blocks is high, the disk data-transfer rate could become a bottleneck

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ Real-time Transactions Systems In a system with real-time constraints, the correctness of the any transactional execution involves both database consistency and the satisfaction deadlines. Most of the time deadlines are the reason why transactional systems perform poorly

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ Long Duration Transaction Traditional concurrency control techniques do not work well when user interaction is required:  Long duration: Design edit sessions are very long  Exposure of uncommitted data: E.g., partial update to a design  Subtasks: support partial rollback  Recoverability: on crash state should be restored even for yet-to-be committed data, so user work is not lost.  Performance: fast response time is essential so user time is not wasted.

DBSQL Copyright © Genetic Computer School, Singapore 2009 Cont’ Transaction Management in Multi-databases Transaction management is complicated in multi-database systems because of the assumption of autonomy Local transactions are executed by each local DBMS, outside of the MDBS system control. and global transactions are executed under multi-database control

DBSQL Copyright © Genetic Computer School, Singapore 2009 End