database design n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Database Design PowerPoint Presentation
Download Presentation
Database Design

Loading in 2 Seconds...

play fullscreen
1 / 12

Database Design - PowerPoint PPT Presentation


  • 69 Views
  • Uploaded on

A presentation for “Cuppa” Corner. Database Design. A trip to First Normal Form. Tony Rogerson, SQL Server MVP http://sql-server.co.uk http://sqlblogcasts.com/blogs/tonyrogerson http://twitter.com/tonyrogerson. Agenda. Introduction to Normalisation Domains Functional Dependencies

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Database Design' - kasa


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
database design

A presentation for “Cuppa” Corner

Database Design

A trip to First Normal Form

Tony Rogerson, SQL Server MVPhttp://sql-server.co.ukhttp://sqlblogcasts.com/blogs/tonyrogerson

http://twitter.com/tonyrogerson

agenda
Agenda
  • Introduction to Normalisation
  • Domains
  • Functional Dependencies
  • Repeating Groups
  • Relation Valued Attributes
  • First Normal Form

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

introduction to normalisation
Introduction to Normalisation
  • Nothing to do with Performance
  • Nothing to do with SQL
  • Nothing to do with Implementation (the Physical)
  • Reduce Data Redundancy
  • Method of putting Data into “Relations”
  • Sets

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

domain is the set of possible values
Domain is “The Set of Possible Values”
  • Examples
    • Colours
      • Red, Green, Blue
    • Age
      • 0 to 180
    • Car Models
      • Jaguar, Ford, Audi
  • May be Finite (colours, age) or Dynamic (Car Models)

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

functional dependency
Functional Dependency
  • Adds Semantics to the data
  • Many to one relationship
  • Left is a candidate key
  • Right can be another key/part of a key/attribute

Determinant(Many)

Dependant(One)

Functionally Determines

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

fd examples
FD Examples

Determinant(Many)

Dependant(One)

Functionally Determines

National Insurance Number

Car Registration Number

VIN

Time of Day

Full Name

Make of Vehicle

Car Registration Number

Type of Meal

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

repeating groups
Repeating Groups

An Attribute having the same meaning and the same “Domain” of values which is repeated, and the placement of values in those repetitions has no meaning and is entirely by chance.

Attribute is AttendeeDomain is {Rosie, Ester, Hazel, Poppy, Joe}

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

repeating groups not
Repeating Groups – Not!

An Attribute having the same meaningand the same “Domain” of values which is repeated, and the placement of values in those repetitions has no meaning and is entirely by chance.

Attribute is Address1, Address2, Address3Domain for Address1 is {Torver} Address2 is {26 Moorla}

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

relation valued attribute
Relation Valued Attribute

Attribute is ?Domain for ?

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

rva expanded
RVA Expanded

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

first normal form
First Normal Form
  • Identify at least one Candidate Key
  • Get rid of Repeating Groups
  • Values must be Atomic (no CSV’s)

Tony Rogerson, SQL Server MVP http://sql-server.co.uk

database design1

A presentation for “Cuppa” Corner

Database Design

Thanks for Listening!

A trip to First Normal Form

Tony Rogerson, SQL Server MVPtonyrogerson@torver.nethttp://sql-server.co.ukhttp://sqlblogcasts.com/blogs/tonyrogerson

http://twitter.com/tonyrogerson