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© 2004 Ken Baldauf, All rights reserved.
Database Systems
Organizing Data in a Database Using Database Systems in
Organizations Emerging Database Trends
Please turn your cell phone off.
© 2004 Ken Baldauf, All rights reserved.
The Value of Databases
Databases and Database Management Systems (DBMS) transform large quantities of data into specific and valuable information for accomplishing some goal.
© 2004 Ken Baldauf, All rights reserved.
File or Table
Database
A collection of data organized to meet user’s needs.
Records (Entities)
Field(Attribute)
© 2004 Ken Baldauf, All rights reserved.
Database Fields
Fields are set to hold specific types of data.
© 2004 Ken Baldauf, All rights reserved.
Keys and Primary Key
Key: A field in a record that is used to identify the record
Primary key: A field that uniquely identifies a record A primary key field prevents duplicate
records from occurring in a table.
© 2004 Ken Baldauf, All rights reserved.
Primary Keys
Which field would act as the best primary key?Which field would act as the best primary key?
© 2004 Ken Baldauf, All rights reserved.
Relational Database
In a relational database, tables are linked (related) through common fields.
© 2004 Ken Baldauf, All rights reserved.
Relation Types One-to-many
Most typical Makes use of primary key
One-to-one Many-to-many
© 2004 Ken Baldauf, All rights reserved.
Northwind Database Example
http://lit.cs.fsu.edu/recitation-notes/nwind.mdb
© 2004 Ken Baldauf, All rights reserved.
In-class Exercise
Database Specification: Build a database to store student grades for Mr. Baldauf’s students There are multiple classes with multiple
sections each with a unique Course Reference Number (CRN)
The courses are divided between multiple recitation instructors identified by SSN
Students identified by SSN
© 2004 Ken Baldauf, All rights reserved.
In-class Exercise
The database should be able to provide the following reports:
© 2004 Ken Baldauf, All rights reserved.
Database Management System (DBMS)
A DBMS consists of a group of programs that manipulate the database and provide an interface between the database and the user.
Front End
DATABASE
Back End
DBMS
SecureAccess
© 2004 Ken Baldauf, All rights reserved.
Database Strengths
Data can be sifted, sorted, queried through the use of data manipulation languages.
The power of a database and DBMS lies in the user’s ability to manipulate the data to turn up useful information.
© 2004 Ken Baldauf, All rights reserved.
Data Manipulation Language
A Data Manipulation Language (DML) is a specific language provided with the DBMS that allows people and other database users to access, modify, and make queries about data contained in the database, and to generate reports.
Structured Query Language (SQL): The most popular DML. SELECT * FROM EMPLOYEE WHERE JOB_CLASSIFICATION = ‘C2”
© 2004 Ken Baldauf, All rights reserved.
Data Stores
Data Warehouse: A database that holds important information from a variety of sources.
Data Mart: A small data warehouse, often developed for a specific person or purpose.
Data Mining: the process of extracting information from a data warehouse. “Connecting the dots”
© 2004 Ken Baldauf, All rights reserved.
Databases and the Internet
The Web is frequently used as the Front End of DBMS’s.
© 2004 Ken Baldauf, All rights reserved.
Media Databases
Databases are increasingly being used to store visual and audio data.
Consider the digital hospital and how it might handle patient records including x-rays.