Database Flashcards Preview

Information and communication technology > Database > Flashcards

Flashcards in Database Deck (22)
Loading flashcards...
1

What is manual database?

Documenting data by hand

2

What is electronic database?

Documenting data on an electronic medium

3

What is database needed for?

To save and retrieve large amounts of data efficiently

4

What are the advantages of a database?

More efficient in retrieving information
Easy to obtain copies
Less physical space required
Data analysis can be done more efficiently
Data can be shared
Independence of data

5

What are the features of database? (6)

Minimal data redundancy
Data consistency
Increases efficiency
Increases accuracy
Increases validity
Security

6

What is data redundancy?

The same data being stored in different tables (enables the maintenance of data consistency)

7

What are the differences between electronic and manual databases?

(Page 256)

8

How is a relational data base introduced?

A collection of fields related to one person or object is called a record
A collection of records is called a database
A collection of related tables is called a relational table

9

What is a primary key?

A column which enables to identify a record uniquely

10

What is a composite primary key?

The primary key which consists of two or more columns of a table uniquely identified as a record

11

What is a foreign key?

A field of one table which is used to uniquely identify rows of another table

12

What are the special features of a foreign table? (3)

Builds a connection between two tables
The related data of the primary key field exists in the other table
Foreign key of one table is the primary key of the other

13

What are the disadvantages of data duplication? (7)

Inability to select a primary key field
Inability to analyse data properly
Reduced efficiency
Possibility of inaccurate data is high
Difficult to enter data
Possibility of making errors in deleting data
Difficulty of updating data

14

What is a data type?

A type of data related to one field

15

What are the different types of data? (5)

Numeric
Text
Currency
Date/Time
Boolean (True/False)

16

What is a Database Management System? (DBMS)

A collection of objects which facilitates planning and maintenance of a database
(Consists of several objects such as tables, queries, forms and reports)

17

What are some examples of DBMS software? (3)

Access (Microsoft Company)
Base (The Document Foundation)
Oracle (Oracle Corporation)

18

What is the process of using a DBMS? (4)

Starting the DBMS software
Planing a data table
Creating the primary key
Entering data

19

What are the different types of relations that can exist among tables? (3)

One-one
One-many
Many-many

20

What is a one-one relationship?

When only a row of a table is related to a row of another table

21

What is a one-many relationship?

When each record of a table is related to several records of the other table

22

What is a many-many relationship?

When a record of a table is related to several records of another table and if a record of that related table is related to several records of the other table