Relational Database Management System

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Transcript Relational Database Management System

Database Management
Data in organizations
and
the data management environment
Managing Data
All the value of this company is in its
people. If you burned down all our
plants, and we just kept our people and
our information files, we should soon be
as strong as ever.
Thomas Watson, Jr. Former chairman of IBM
Data, Information, & Knowledge
Data
Watson: “raw, unsummarized, and unanalyzed facts.”
Information
Watson: “data that have been processed into a meaningful
form.”
Knowledge
Watson: “the capacity to use information… the expertise to
make sense of… information… to interpret information and
use it in decision making.”
Information is created from streams of data
through the application of knowledge.
Data – functions and impact through time…
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Data facilitate business events, such as
transactions, in the present.
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Data produced during prior events constitute
an historical record of the past that can be
summarized, explored, and analyzed for
insights...
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… which, in turn, informs decision-making that
shapes the future.
Management of data
Desirable attributes:
Typical problems:
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shareable
transportable
secure
accurate
timely
relevant
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redundancy
inconsistency
lack of control
access problems
- poor interfaces
- long delays
lack of richness
lack of integration
Individual data management
• Internal memory is limited
• External memory extends internal memory
Calendar
• Organizing principles
– Set amount of space
– Ordering
– Rapid access
December 25, 1852
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Staff Meeting
Email Communication
Project Planning
Check lunch preparations
1 Meeting with directory
2 Vendor presentation
3
4 Process paperwork
5
6 Drive home
7 Dinner
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9 Reading and relaxation
© 1803, The Expeditioner, London
Address book
• Organizing principles
– Pre-formatted storage
space
– Ordering
– Rapid access
K-L
Name
Address
Rudyard Kipling
PO Kyhber Pass
Northwest Frontier
India
Name
Address
Jack London
PO Klondike
Alaska
Name
Address
Name
Address
© 1815, The Expeditioner, London
K
L
To do list
• Organizing principles
– Structure
– Rapid scan support
To Be Done This Week
Action List
√
Explore Nile
Shoot crocodile
Write journal
√
Unwrap mummy
© 1823, The Expeditioner, London
(In data management, computer databases are
just part of the picture… )
Organizational memory is supported by:
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relational databases
other “database” technology
- DBs based on older technology
(our focus)
- object databases
- spreadsheets
- PDAs and cell phones
- voicemail, email, groupware
- on-line documents
paper records
multi-media artifacts
formal decision models
employees’ brains
organizational procedures and routines
systems applications
Data management
systems timeline
Object-oriented DBMS
Relational DBMS
Network DBMS
Hierarchical DBMS
File systems
1950
1960
1970
1980
1990
2000
Flat File Database
Name
Address
Course
Grade
Mark Freeman
123 Main St
English 101
B
Mark Freeman
123 Main St
Data Structure
A
Mark Freeman
123 Main St
Psych 101
C
Mary Smith
413 Elm Dr
Chemistry 200
A
Mary Smith
413 Elm Dr
French 205
B
David Cole
1009 10th Apt B Accounting
102
A
Hierarchical Database
Network Database
Network and Hierarchical
• Redundant
• Difficult to maintain
– Required system-level understanding of
underlying data structures to access data
• Costly
– Labor
– Computer resources
– Time
Relational Databases
• E F Codd, 1970
• Relational
– Relations = Grouping of related data (tables)
– Data stored only once
– Query language for accessing data
– Analysts no longer need know how data is stored!
• RDBMS (Relational Database Management System)
IT Org Chart
CIO
Operations
Director
Database
Manager
Data Center
Manager
Database
Administrator
Support
Manager
Application
Development
System
Administrator
Technical
Support
Database
Architect
Network
Administrator
Application
Support
Database
Programmer
Information Technology Roles
• Database Administrator
– Manages day-to-day operations, install,
upgrade, data backup recovery
• Data Architect
– Designs the database
– Works with a business analyst to choose
what data to store and how to organize it
• Database Programmer
– Develops database applications: computer
programs that allow users to retrieve and
process data
Data Modeling – Top-down approach
Data Model
Data Definition
Database Table
The database development lifecycle (DDLC)…
and the Term Project Assignments
Completed by
Instructor
PROJECT
PLANNING
Assignment 1:
Database Dictionary
REQUIREMENTS
DEFINITION
Assignment 3:
SQL Queries
DESIGN
CONSTRUCTION
IMPLEMENTATION
Assignment 1:
Data Model
USE
Assignment 2:
Database Prototype
EVOLUTION
Database Management Systems
• OLTP (Online Transaction Processing)
– Many transactions
– Short transactions
– Volatile data
• Decision Support
– Data Warehouse, Data Mining
– Fewer transactions
– Longer transactions
– Static data
Database Management System
Design
Design decisions have significant future
impact
Reliability
Scalability
Security