1. Chapter 12 Accessing Databases

2. Practical PC 5th Edition Chapter 12
Getting Started
In this Chapter, you will learn:
What’s a database
About database software
How to create your own database
To create databases with spreadsheet software
About databases on the Web and on CDs
About Hardware: CDs and DVDs
Practical PC 5th Edition Chapter 12

3. Practical PC 5th Edition Chapter 12
What’s a database?
A database is a collection of data
Structured databases contain information that is organized as fields, records, and files
A field contains a single piece of information
A record contains fields of information about a single “entity” in the database
A group of similarly structured records form a fie
A relational database allows you to store information for two or more different types of records and form a link between them
Each record type is stored in a table
For example, a video store database may include a table of customers and a table of videos
When a customer checks out a video a link is made between the two tables
Practical PC 5th Edition Chapter 12

4. Practical PC 5th Edition Chapter 12
What’s a database?
Database with linked tables
Practical PC 5th Edition Chapter 12

5. Do I need database software?
Database software provides a set of tools to enter and update information in fields
Also called a database management system
You can enter, delete, sort, and search for records
You might access a product database when shopping online or a bank database at an ATM machine
Database software offers a wealth of data management capabilities
Requires a substantial learning commitment
For simple files, you may be able to use the database modules in Microsoft Works
You can also use spreadsheet software for simple databases
Practical PC 5th Edition Chapter 12

6. How would I create my own database?
Creating a database consists of two tasks:
Creating the file structure to hold the data
Entering the data
A file structure is a specification for the database fields and their characteristics
You’ll need to assign a name to each field
You may also need to specify the data type and maximum field length
You then enter the data carefully and consistently
Be consistent with symbols, capitalization, categories, and abbreviations
Compare onscreen data against the original documents
Practical PC 5th Edition Chapter 12

7. How would I create my own database?
Entering data in Access
Practical PC 5th Edition Chapter 12

8. Can I really create databases with spreadsheet software?
You can use spreadsheet software to maintain files of information
You cannot use it to join files or tables together to create a relational database
You can use the Form View feature in spreadsheet software to view each row as a “card” containing a series of fields
You can also filter the data, which is more complicated, but useful for creating reports that show only selected data
Practical PC 5th Edition Chapter 12

9. What about databases on the Web and on CDs?
You’ll find many databases on the Web
Look up your old roommate in a phone-book-style database
Look up flights in a database of flight schedules
Check the value of your car in a digital “Blue Book”
Web and CD databases can overlap
Web is optimal for data that is constantly changing
On the Web databases can actively collect information
CDs provide a low cost distribution method for less changeable data
CDs are more private since your access of the data is not tracked by a cookie or a Web site
Practical PC 5th Edition Chapter 12

10. What about databases on the Web and on CDs?
Web and CD databases
Practical PC 5th Edition Chapter 12

11. Practical PC 5th Edition Chapter 12
Hardware: CDs and DVDs
CDs
Originally invented to hold music
CD-ROM
Computer CDs are sometimes called CD-ROMs to distinguish them from audio CDs
CD-ROM is an abbreviation of “compact disc read-only memory”
CD-ROMs are preloaded with data and cannot be used to store additional data
Practical PC 5th Edition Chapter 12

12. Practical PC 5th Edition Chapter 12
Hardware: CDs and DVDs
CDs (continued)
CD-R and CD-RW
CD-R (CD-recordable) data cannot be changed once it is recorded
CD-RW (CD-rewritable) allows you to record and then later change the data
CD-Rs are considered to be more dependable since some machines have trouble reading CD-RWs created on other machines
Most CD drives have R and RW capabilities, and the speeds of the drives vary
Practical PC 5th Edition Chapter 12

13. Practical PC 5th Edition Chapter 12
Hardware: CDs and DVDs
CD Drive Speed Varies
Practical PC 5th Edition Chapter 12

14. Practical PC 5th Edition Chapter 12
Hardware: CDs and DVDs
DVDs
Originally invented to replace VHS tapes
Digital Video Disc
Storage capacity much greater than a CD-ROM disc
Data can be stored in one of four formats depending on number of sides and number of layers used
DVDs are available in read-only, recordable, and rewritable formats
High Definition DVD is a high-capacity DVD format designed for high definition videos and data storage
Practical PC 5th Edition Chapter 12

15. Hardware: CDs and DVDs
DVD storage capacity depends on sides and layers used
Practical PC 5th Edition Chapter 12

16. Practical PC 5th Edition Chapter 12
Hardware: CDs and DVDs
Blu-ray disk is a competing format to High Definition DVDs
DVD drives often work with more than one type of optical media
DVD+R/RW / CD-R/RW combination drive can read and record on both DVDs and CDs
Most new PCs include a combination drive
Practical PC 5th Edition Chapter 12

17. Who owns information about me?
What do you think?
Can you identify an actual incident when you discovered that data about you had been distributed without your approval?
Do you accurately fill out questionnaires that you encounter on the Web?
Do you think that you have the right to be consulted before anyone distributes information about you?
Practical PC 5th Edition Chapter 12

18. Practical PC 5th Edition Chapter 12
Chapter Summary
You should now be able to:
Understand what is a database
Use database software
Create your own database
Create databases with spreadsheet software
Understand about databases on the Web and on CDs
Understand the difference CDs and DVDs
Practical PC 5th Edition Chapter 12