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Database Types

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Title: Database Types


1
Database Types
  • Warren Kawano
  • Jason Kim
  • Toshie Kuwabara
  • Jessica May
  • October 18, 2002

2
AGENDA
  • History/Background of Databases
  • Hierarchical
  • Network
  • Relational
  • Object-Oriented
  • Object-Relational

3
Introduction
  • IBM started work on databases in the 1970s
  • Honeywell first to create database programs
  • Constantly updating
  • Hierarchical, object oriented, network, and
    relational databases

4
Hierarchical Databases
  • First databases developed 1960s
  • Hierarchical Structure
  • Genealogy, parent-child
  • One-one relationship
  • One-many relationship

5
http//www.wdvl.com/Authoring/DB/Intro/heirarchica
l_databases.html
6
Problems with Hierarchical Structure
  • No many-many relationship
  • Difficult to find information unless you know the
    whole database

7
Network database model
  • Designed to solve the problem of data redundancy
    with the Hierarchical database model.
  • Is a database model which organizes relationship
    of data in a net-like fashion.

8
Network database that contains information on
professors, classes, and students.
Dr.C
Dr.A
Dr.B
Professors

bus311
bus312
classes
bus310
Student A
Student B
students
Student C
Set composed of at least two record types, an
owner(parent) and a record(child).
9
Advantages and Disadvantages
  • Advantages
  • Data is accessed very quickly.
  • Users can access data starting with any table.
  • It is easier to model more complex data bases.
  • It is easier to develop complex queries to
    retrieve data.
  • Disadvantages
  • The structure of the database is not easily
    modified.
  • changes to the database structure definitely
    affect application programs that access the
    database.
  • The user has to understand the structure.

10
Data
  • Records
  • -sets of related data values
  • Record types
  • -sets of records of same type
  • Set types
  • -relationships between two record types

11
Relational Database
  • Developed in the 1980s
  • Most common form of database today
  • Data is arranged in a table, called a relation,
    with rows and columns

12
Sample relationcolumns attributesrows tuple
13
Relational Database
  • Think of it as a file cabinet
  • Each drawer is a table

14
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15
Relational Database (cont.d)
  • A group of related tables (relations)
  • Each relation is labeled (title)
  • Each also has a column or columns called the
    primary key, which uniquely identifies the row in
    the table

16
Finding the Primary key
17
Object-Oriented Database
  • Different from others because it stores data AND
    INSTRUCTIONS together in the database
  • The combination of data and instructions is
    called an object
  • Not in widespread use

18
Object-Relational Database
  • Recent development but not new technology
  • Combines object-oriented capabilities with
    relational databases
  • Copes with all the new types of data
  • Alternative to completely changing the database
    system

19
Conclusion
  • Important for businesses
  • Each type of database serves its own purpose
  • Fine tuning leads to bigger and better things

20
Database Types
  • Hierarchical
  • -parent/child
  • Network
  • -net-like
  • Relational
  • -stored in relations (tables)
  • Object-Oriented
  • -stored as an object
  • Object-Relational
  • -combines object and relational

Warren Kawano Jason Kim Toshie Kuwabara Jessica
May Oct. 18, 2002
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