1. Data is often in the form of facts or figures of information e.g. numbers, text, images, and sounds, in a form that is suitable for storage.
2. Information is the definite knowledge acquired or supplied about something or somebody. It can also be the collected facts and data about a specific subject. E.g.
3. A database is used for to arranged collection of data where it can be managed to create, store and manipulate information efficiently.
4. Paper survey
5. Library books database
6. Field: Information such as characters or numbers can be entered and manipulated. E.g. author, the title, and the subject headings
Record: a collection of related items of information. E.g. An account of an employee
File: a uniquely named collection of program instructions or data stored on a hard drive. E.g. the name of the data searched in a library database
7. The main purpose of a primary key is to implement a relationship between two tables in a relational database
Student name No
Student address No
Student number Yes, because student all have unique numbers and is a quicker way to search a specific data
Student DOB No
Student’s form No
Car model
Car make
Colour
Registration number: Yes, because every car has a unique number registered onto the car
Number of doors
8. The difference between a flat-file database and a relational database is that flat-file presents records in single line and Fields from each record may simply have a fixed width with padding. A relational database is defined as a set of tuples that all have the same attributes. This is usually represented by a table, which is data organized in rows and columns.
9.
Alphanumeric (text): Text and text with numbers combined
Number: Numbers including those with decimal places
Currency: Currency values and numeric data used in mathematical calculations involving data Date/Time: Date and time values
Logical/ Boolean/ Yes No: Yes and No values and fields that contain only one of two values
Autonumber: A unique sequential (incremented by 1) number or random number assigned
Give an example for the following datatypes
Alphanumeric (text) Postcode – CV64 3RT
Number Age – 13
Currency Dollars – $50
Date/Time Date borrowed – 20/02/08
Logical/ Boolean/ Yes No Agree or disagree – tick box
Autonumber Student ID
Which would be the most appropriate datatype for the following?
£15.99 Currency
NQTR56N8J Text
15, Pear Tree Avenue Address
14th November 2002 Date/time
Male Female Logical
16 number
10. it is important to have an appropriate length of field because data can be useless or exceed sufficient information
Decide which would be appropriate field lengths for the following fields
Gender (male/female) 6
Forename 20
House number and street name 15
Postcode 4
Telephone number 10
11. Database validation involves checking the database file to ensure that the various data structures retain their integrity and internal consistency
12. rule stating that the quality of the output is a function of the quality of the input; put garbage in and you get garbage out
13. Testing the comfirm that the system, subsystem or components must documented requirements or specification on the design
14.
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Males, females
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M F
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Green, Red, Blue, Brown
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G R Bl Br
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Ford, Volkswagen, Honda, toyota
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Frd Volk Hon Toy
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Think of two advantages of coding data
- To reduce the amount of data input
- Creates shortcuts
Think of a disadvantage of coding data
- The codes could have common data
15. Explain how you could search for data in a database and give an example
From using queries, we could link up a particular data. In a patient’s database, you could identify what’s the patient’s age, sex or address.
