Web - Distributed& Parallel DBMS M Tamer Özsu Page 9.1 Outline Introduction Distributed DBMS Architecture Distributed Database Design

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Distributed & Parallel DBMS M. Tamer Özsu Page 9.1 Outline ¡ Introduction ¡ Distributed DBMS Architecture ¡ Distributed Database Design ¡ Distributed Query Processing ¡ Distributed Transaction Management ¡ Data Replication ¡ Parallel Database Systems ¡ Data Integration Systems ¢ Web Search/Querying z Web Models z Web Crawling z Retrieval, Querying, Ranking, Indexing z Searching the Hidden Web ¢ Peer-to-Peer Data Management ¢ Data Stream Management Distributed & Parallel DBMS M. Tamer Özsu Page 9.2 Acknowledgements ¡ These slides and the survey they are based on were prepared by the following students at University of Waterloo as part of CS856 – Web Data Management z Issam Alazzoni z Aseem Cheema z Amr El-Helw z E. Cem Sözgen z Ali Taleghani z Yasemin Ugur-Özekinci Distributed & Parallel DBMS M. Tamer Özsu Page 9.3 Introduction ¡ The Web has more than 3 billion HTML pages. ¡ Most Internet users gain access to the Web using search engines. ¡ 23% of Web pages change daily [3]. ¡ 40% of commercial pages change daily [3]. Distributed & Parallel DBMS M. Tamer Özsu Page 9.4 Properties of Web Data ¡ Lack of a schema z Data is at best “semi-structured” z Missing data, additional attributes, “similar” data but not identical ¡ Volatility z Changes frequently z May conform to one schema now, but not later ¡ Scale z Does it make sense to talk about a schema for Web? z How do you capture “everything”? ¡ Querying difficulty z What is the user language? z What are the primitives? z Aren’t search engines or metasearch engines sufficient? Distributed & Parallel DBMS M. Tamer Özsu Page 9.5 Properties of Web Data ¡ Lack of a schema z Data is at best “semi-structured” z Missing data, additional attributes, “similar” data but not identical ¡ Volatility z Changes frequently z May conform to one schema now, but not later ¡ Scale z Does it make sense to talk about a schema for Web? z How do you capture “everything”? ¡ Querying difficulty z What is the user language? z What are the primitives? z Aren’t search engines or metasearch engines sufficient? Distributed & Parallel DBMS M. Tamer Özsu Page 9.6 Data Delivery on the Internet ¡ Properties of information supply z It is very large in volume z It is highly heterogeneous z May not have a properly defined schema z Data available from too many devices and in streaming fashion ¢ Data stream systems ¡ Properties of information consumption z It is data intensive ¢ Use of large data sets is common z It requires access to diverse data sources ¢ Existing databases and/or repositories must somehow be “glued” together ¢ Application integration Distributed & Parallel DBMS M. Tamer Özsu Page 9.7 Properties of Web Data ¡ Lack of a schema z Data is at best “semi-structured” z Missing data, additional attributes, “similar” data but not identical ¡ Volatility z Changes frequently z May conform to one schema now, but not later ¡ Scale z Does it make sense to talk about a schema for Web?Does it make sense to talk about a schema for Web?...
View Full Document

This note was uploaded on 12/23/2009 for the course DBST 663 taught by Professor Tba during the Spring '09 term at MD University College.

Page1 / 63

Web - Distributed& Parallel DBMS M Tamer Özsu Page 9.1 Outline Introduction Distributed DBMS Architecture Distributed Database Design

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online