Databases

1. What is a database?

A database is a structured collection of records or data that is stored in a computer system.

2. Name three types of information products that may be produced using a database.

• Spatial Information
• Compressed Information
• Stringed/continuous information

3. How does a database manage information?

It organises it into different categories.

4. Provide three examples for each common data type.

• Integer: byte, word, octet
• Floating-point numbers (decimals): any rational number, Pi, binary system.
• Alphanumeric strings: Letters stringing to represent numbers (i.e. S=0, 1), a binary string, a variable.

5. In a CD collection database, name five of the fields that may be used. For each field describe the data type that each field will contain. Using details about your favourite artist and CDs, make up some data that might be used in each of these fields. Then describe and write out what a record in this database may look like.

Artist: Text, (Notis Sfakianakis, Greek singer)

Year: Number, (1998)

Title/name of CD: Text, (From Saloniki)

CD Number: Number, (CD Number 1)

If it’s borrowed or not: Text (Currently not borrowed)

The information in the brackets above is about a Greek CD I own. A record for it would look something like that. The CD has never been borrowed from me or my Dad and we have owned it since when it was first released back in 1998.

6. What is meant by the phrase "data has integrity"?

It means that the data is in a logically consistent order.

7. Why is it important that data has integrity?

So that it can be managed and altered at any given time and can be viewed in a proper order when needed.

8. Explain the meaning of the term 'data'. Give three examples of data that may be input to a computer.

Data refers to information or facts usually collected as the result of experience, observation or experiment, or processes within a computer system, or premises.

3 examples are:

• Numbers
• Words
• Images

9. What is the difference between primary and secondary data sources? Give examples of each.

Primary data: (Also known as Raw Data) Data that has not been processed for use. It can refer to the binary data on electronic storage devices such as hard disk drives (also referred to as low-level data).

Secondary Data: Secondary data is collecting and processing data by people other than the researcher in question. Common sources of secondary data for include censuses, large surveys, and organizational records.

-Stelman257

The 9 different data steps.

ACQUISITION
Jenny acquires data each week by recording on paper the amount raised and the date.
INPUT
She then inputs this data into the spreadsheet using the keyboard.
VALIDATION
The data is validated by inbuilt formulas that check the amount is reasonable.
MAIPULATION
The data for each week is manipulated using a formula to total the amounts.
STORAGE
The file is saved to the hard drive after processing.
RETRIEVAL
On the next collection day, the file is retrieved and new data added.
OUTPUT
Output in the form of a printout is obtained at the end of each month.
COMMUNICATION
Copies are printed, communicating the information to all students by hand.
DISPOSAL
At the end of they ear, when the file is no longer needed, Jenny deletes the file from her computer.

-Stelman257

Nintendo announce the DSi

Nintendo have recently announced a new version of the Nintendo DS, Called the Nintendo DSi. The DS Lite and DS have both had GBA slots, however it seems the DSi will not have one instead making itself thinner but with a while range of other improvements as well.


The handheld's screens have been enlarged, and will now be 17% bigger (at 3.25 inches) than those found on the DS Lite. As for the rumoured additions, both have proven to be correct, with "audio enhancements" made to the handheld, while it will also now include a .3 megapixel (640x480) camera. And that's just the start of it.

The DSi also features an SD memory card slot, making it possible to take pictures with the DSi and then view them on the Nintendo Wii. Though i personally think that most of this will be used more for pirating than actual photo taking. There's also going to be an in-built internet browser on the DSi, and it's possible to download games and keep them on the DSi with this (again i think it will be used for pirating).

For digital delivery purchases, there is a DSi Shop, from which users can download DSiWare from. Basically these are little games that can be bought for a small price.

Pricing categories for the DSiWare will be: Free, 200 points, 500 points and "Premium" or 800 points. Customers will get 1000 free points to spend at the DSi Shopjust by buying the product. The DSi will be available in two colours, white and black.

Nintendo has stated that it will be released in all countries around mid-year 2009, for around $250.00AU. Personally myself i think that if they put enough variety in the shop, and make video games make use of the camera, it could be successful. I mean I'd buy it. But we'll have to see.

-Stelios Liousas