Building Trustworthy Semantic Webs Dr Bhavani Thuraisingham The University of Texas at Dallas Lecture 3 Supporting Technologies Databases Information Management and Information Security August 2006 Database System Consists of database hardware Database Management System DBMS and users Database is the repository for persistent data Hardware consists of secondary storage volumes processors and main memory DBMS handles all users access to the database Users include application programmers end users and the Database Administrator DBA Need Reduced redundancy avoids inconsistency ability to share data enforce standards apply security restrictions maintain integrity balance conflicting requirements We have used the definition of a database management system given in C J Date s Book Addison Wesley 1990 An Example Database System Application Programs Database Management System Database Adapted from C J Date Addison Wesley 1990 Users Metadata Metadata describes the data in the database Example Database D consists of a relation EMP with attributes SS Name and Salary Metadatabase stores the metadata Could be physically stored with the database Metadatabase may also store constraints and administrative information Metadata is also referred to as the schema or data dictionary Functional Architecture Data Management User Interface Manager Schema Data Dictionary Manager metadata Query Manager Security Integrity Manager Transaction Manager Storage Management File Manager Disk Manager DBMS Design Issues Query Processing Optimization techniques Transaction Management Techniques for concurrency control and recovery Metadata Management Techniques for querying and updating the metadatabase Security Integrity Maintenance Techniques for processing integrity constraints and enforcing access control rules Storage management Access methods and index strategies for efficient access to the database Relational Database Example Relation S S S1 S2 S3 S4 S5 SNAME Smith Jones Blake Clark Adams Relation SP STATUS CITY 20 London 10 Paris 30 Paris 20 London 30 Athens Relation P P P1 P2 P3 P4 P5 P6 PNAME Nut Bolt Screw Screw Cam Cog COLOR WEIGHT CITY Red 12 London Green 17 Paris Blue 17 Rome Red 14 London Blue 12 Paris Red 19 London S S1 S1 S1 S1 S1 S1 S2 S2 S3 S4 S4 S4 P P1 P2 P3 P4 P5 P6 P1 P2 P2 P2 P4 P5 QTY 300 200 400 200 100 100 300 400 200 200 300 400 Concepts in Object Database Systems Objects every entity is an object Example Book Film Employee Car Class Objects with common attributes are grouped into a class Attributes or Instance Variables Properties of an object class inherited by the object instances Class Hierarchy Parent Child class hierarchy Composite objects Book object with paragraphs sections etc Methods Functions associated with a class A Definition of a Distributed Database System A collection of database systems connected via a network The software that is responsible for interconnection is a Distributed Database Management System DDBMS Each DBMS executes local applications and should be involved in at least one global application Ceri and Pelagetti Homogeneous environment Architecture Database 1 Database 3 DBMS 3 Distributed Processor 3 Site 3 DBMS 1 Distributed Processor 1 Communication Network Site 1 Database 2 Distributed Processor 2 DBMS 2 Site 2 Data Distribution SITE 1 EMP1 DEPT1 SS Name Salary D D Dname MGR 1 2 3 4 5 6 John Paul James Jill Mary Jane 20 30 40 50 60 70 10 20 20 20 10 20 10 C Sci Jane 30 English David 40 French Peter SITE 2 EMP2 SS 9 Name Mathew Salary 70 D 50 7 Davi d 80 30 8 Peter 90 40 D DEPT2 Dnam e 50 Math John 20 Physics Paul MGR Interoperability of Heterogeneous Database Systems Database System A Database System B Relational Transparent access to heterogeneous databases both users and application programs Query Transaction processing ObjectOriented Network Database System C Legacy Federated Database Management Database System A Database System B Federation F1 Cooperating database systems yet maintaining some degree of autonomy Federation F2 Database System C Federated Data and Policy Management Data Policy for Federation Export Data Policy Export Data Policy Export Data Policy Component Data Policy for Agency A Component Data Policy for Agency C Component Data Policy for Agency B Current Status and Directions Developments Several prototypes and some commercial products Tools for schema integration and transformation Standards for interoperable database systems Challenges being addressed Semantic heterogeneity Autonomy and federation Global transaction management Integrity and Security New challenges Scale Web data management What is Information Management Information management essentially analyzes the data and makes sense out of the data Several technologies have to work together for effective information management Data Warehousing Extracting relevant data and putting this data into a repository for analysis Data Mining Extracting information from the data previously unknown Multimedia managing different media including text images video and audio Web managing the databases and libraries on the web Data Warehouse Users Query the Warehouse Oracle DBMS for Employees Data Warehouse Data correlating Employees With Medical Benefits and Projects Sybase DBMS for Projects Could be any DBMS Usually based on the relational data model Informix DBMS for Medical Multidimensional Data Model ProjectName Name Project ProjectLeader Leader Project Years Years Months Months Weeks Weeks ProjectSponsor Sponsor Project ProjectCost Cost Project ProjectDuration Duration Project Dollars Dollars Pounds Pounds Yen Yen Data Mining Information Harvesting Knowledge Mining Data Mining Knowledge Discovery in Databases Data Dredging Data Archaeology Data Pattern Processing Database Mining Siftware Knowledge Extraction The process of discovering meaningful new correlations patterns and trends by sifting through large amounts of data often previously unknown using pattern recognition technologies and statistical and mathematical techniques Thuraisingham 1998 Multimedia Information Management Video Source Broadcast News Editor BNE Scene Change Detection Frame Classifier Imagery Silence Detection Correlation Story GIST Theme Broadcast Detection Commercial Detection Key Frame Selection Story Segmentation Audio Closed Caption Text Speaker Change Detection Closed Caption Preprocess Segregate Video Streams Broadcast News Navigator BNN Token Detection Named Entity Tagging Analyze and Store Video and