1 / 24

Database Architecture Models and Design

Database Architecture Models and Design. Ian Horrocks Carole Goble John Sargeant Simon Harper. Contact Details & Resources. Ian Horrocks Room 2.75 < Horrocks@cs.man.ac.uk > Carole Goble Room 2.28 < Carole@cs.man.ac.uk > Simon Harper (lab) Room 2.120a < sharper@cs.man.ac.uk >

minty
Download Presentation

Database Architecture Models and Design

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Database Architecture Models and Design Ian Horrocks Carole Goble John Sargeant Simon Harper

  2. Contact Details & Resources • Ian Horrocks • Room 2.75 <Horrocks@cs.man.ac.uk> • Carole Goble • Room 2.28 <Carole@cs.man.ac.uk> • Simon Harper (lab) • Room 2.120a <sharper@cs.man.ac.uk> • John Sargeant • Room 2.69 <jsargeant@cs.man.ac.uk> • http://www.cs.man.ac.uk/~horrocks/cs2312/

  3. Objectives • Raise awareness about databases, database design and database management systems • Enable you to design and use a database to support an application • To understand the implications of your design • To realise that designing databases is non-trivial and requires imagination, flexibility and thought

  4. Introduction and motivation A database model Relational database model Integrity Oracle DBMS SQL and Embedded SQL Database design Logical design Conceptual design Mapping conceptual to logical Pragmatic issues Physical design Integrity and correctness Architecture of DBMS Client-server Open architectures Transaction Processing Multi-user & Concurrency Resilience & Recovery CS2311 Course Structure

  5. Use, design and build a database to support a holiday booking system Oracle 8i DBMS Example classes and labs integrated Exercise 1 & 2 individually Exercise 3 & 4 as pairs Sweeney Tours Laboratory Exercise: Sweeney Tours

  6. IMPORTANT ATTENDANCE POLICY • You are required to attend Lab Classes, if you attend you will be given an Automatic Extension to submit at the start of the following weeks example class. If you do not attend you will be given NO extension and you will be expected to submit by the end of the Lab Class and no extension will be forthcoming. There may be exceptional circumstances as to why you did not attend the Lab Class or Hand in by the Automatic Extension date. These cases will be examined individually BUT we are very strict on attendance and handing in deadlines. You should note that we find there is a definite correlation between the people who attend Lab Classes and Examples Classes and those that pass their exams.

  7. Recommended Texts • Elmasri and Navathe • Fundamentals of Database Systems • 3rd Edition, Addison Wesley • Atzeni, Ceri, Paraboschi and Torlone • Database Systems: Concepts, Languages an Architectures • MacGraw Hill • Ullman and Widom • A First Course in Databases • Garcia-Molina, Ullman and Widom • Database Systems: The Complete Book

  8. What is a database? a structured collection of information captures the semantics of an application • Logically coherent—so it makes sense • Inherent meaning—information vs data • Specific purpose—intended user group • Representation of the real world—changes in the real world reflected in the database

  9. What is a Database Management System? a collection of programs and tools to create & maintain a database • Defining specifying types of data • Constructing storing & populating • Manipulating querying, updating, reporting

  10. Actors DBMS Designers and Implementers Database Administrator End Users DBA • casual • ‘parametric’ or ‘canned’ transactions • sophisticated Database Designers Database Operators and Maintenance Tool Developers Personnel Database Management System

  11. Structure data types data behaviour Persistence store data on secondary storage Retrieval a declarative query language a procedural database programming language Performance retrieve and store data quickly Correctness Sharing concurrency Reliability and resilience Large volumes Characteristics of a Database

  12. File Management Systems: a physical interface Student Year Lists Student Data Admin Course Data Timetable Scheduler Lecturer Data Payroll Cheques

  13. File Management Systems: Sharing data and operations Student Admin Student Data Lab Timetable Tutorials Course Data Scheduler Teaching Lecturer Data Schedule Payroll

  14. Sharing data:replication—redundancy Student Admin Student Data Lab Timetable Course Data Tutorials Lecturer Data Scheduler Teaching Schedule Payroll

  15. DBMS: A Logical Interface Lab University Database Timetable Data Database Teaching course Management Schedule student System lecturer Tutorials Data Dictionary or System Catalog University Database Metadata ?QUERIES

  16. File Management Systems • Uncontrolled redundancy • Inconsistent data • Inflexibility • Limited data sharing • Poor enforcement of standards • Low programmer productivity • Excessive program maintenance • Excessive data maintenance

  17. Controlled redundancy consistency of data & integrity constraints Integration of data self-contained & represents semantics of application Data and operation sharing multiple interfaces Services & Controls security & privacy controls backup & recovery enforcement of standards Flexibility data independence data accessibility reduced program maintenance Ease of application development Database Management System Approach

  18. more expensive more complex general simple stringent real-time single user static Summary: In a file management system is data is PHYSICALLY accessed and UNINTEGRATED In a database management system data is LOGICALLY accessed and INTEGRATED a data dictionary a query language However....

  19. Simplified Environment(from Elmasri & Navathe) Users/Programmers Database System Application Programs/Queries DBMS Software Software to Process Queries / Programs Software to Access Stored Data Stored Database Definition Stored Database (Metadata)

  20. Interfaces to a Data Dictionary Database Application End Users Administrators Programmers Human Interfaces Data Dictionary Software and DBMS Interfaces Integrity Compilers / Application Programs / Constraint Precompilers Report Generators Enforcer

  21. Model A structure that demonstrates all the required features of the parts of the real world which is of interest to the users of the information in the model. Representation and reflection of the real world (Universe of Discourse) Data Model A set of concepts that can be used to describe the structure of a database: the data types, relationships, constraints, semantics and operational behaviour. It is a tool for data abstraction A model is described by the schema which is held in the data dictionary. Models and Schemas Student(studno,name,address) Course(courseno,lecturer) Student(123,Bloggs,Woolton) (321,Jones,Owens) Schema Instance

  22. Sharing—Multiple views of data DataBase Management System Database

  23. Data Independence New functions New Change in hardware use New users New data Database User's view Change in New storage technology Linkage to other techniques databases • Logical data independence • change the conceptual schema without having to change the external schemas • Physical data independence • change the internal schema without having to change the conceptual schema

  24. Ansi-Sparc Database Architecture End Users External External External External Level View A View B View N external/conceptual mapping Conceptual Schema Conceptual Level conceptual/internal mapping Internal Level Internal schema Stored Database

More Related