Transcript Slide 1

Background
Prepared by:
Mr. Mahmoud Rafeek Alfarra
Copyright © 2011 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Outline
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Traditional File-based System
Limitations of the File-based System
Important definitions
Database management system
Components of the Database Environment
Evolution of DB Systems
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Traditional File-based System
 File based system is a collection of application
programs that perform services for the endusers.
 Each program defines and manages its own data.
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Limitations of the File-based System
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Separation and isolation of data.
Duplication of data.
Data dependence.
Incompatibility of files.
Fixed quires of application programs.
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Important definitions
 Database: organized collection of logically related
data.
 Data: stored representations of meaningful
objects and events
 Structured: numbers, text, dates
 Unstructured: images, video, documents
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Important definitions
 Information: data processed to increase
knowledge in the person using the data.
 Metadata (data dictionary, system catalog): data
that describes the properties and context of user
data.
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Database management system
 A software system that is used to create,
maintain, and provide controlled access to user
databases.
DBMS manages data
resources like an
operating system
manages hardware
resources
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Workgroup database with local area network
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Workgroup database with local area network
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Components of the Database Environment
 CASE Tools – computer-aided software
engineering
 Repository – centralized storehouse of metadata
 DBMS – software for managing the database
 Database – storehouse of the data
 Application Programs – software using the data
HW1: Represent the components of DB envi. Using
meaningful Drawing.
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Components of the Database Environment
 User Interface – text and graphical displays to
users
 Data Administrators – personnel responsible for
maintaining the database
 System Developers – personnel responsible for
designing databases and software
 End Users – people who use the applications
and databases
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Components of the Database Environment
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Evolution of DB Systems
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Flat files - 1960s - 1980s
Hierarchical – 1970s - 1990s
Network – 1970s - 1990s
Relational – 1980s - present
Object-oriented – 1990s - present
Object-relational – 1990s - present
Data warehousing – 1980s - present
Web-enabled – 1990s - present
Copyright © 2011 Ramez Elmasri and Shamkant Navathe
Thank You…
Question ?!
Copyright © 2011 Ramez Elmasri and Shamkant Navathe