Chapter 9 Databases: Unit 9.1: Databases

Question 1

Define database

Answer 1

Structured collection of data that allows people to extract information in a way that meets their needs.

Question 2

What types of data can be stored in a database?

Answer 2

Text, numbers, pictures; anything that can be stored on a computer.

Question 3

Define single-table database

Answer 3

Database that contains only one table.

Question 4

Why are databases useful?

Answer 4

Prevent problems occurring because:
If any changes or additions are made it only has to be done once - data is consistent
The same data is used by everyone
Data is only stored once in relational databases which means no data duplication.

Question 5

What are databases used for?

Answer 5

To store information about people, things, events, etc.

Question 6

Define record

Answer 6

A row in a table

Question 7

Define field

Answer 7

A column in a table

Question 8

What are the 6 data types?

Answer 8

Text/alphanumeric
Character
Boolean
Integer
Real
Date/Time

Question 9

Define SQL

Answer 9

Standard Query Language for writing scripts to obtain useful information from a database.

Question 10

Define SQL script

Answer 10

List of SQL commands that perform a given task, often stored in a file so the script can be reused.

Question 11

What are the 6 SQL Query statements?

Answer 11

SELECT - Fetches specified fields (columns) from a table
FROM - Identifies the table to use
WHERE - Includes only records (rows) in a query that match a given condition
ORDER BY - Sorts the results from a query by a given column either alphabetically or numerically
SUM - Returns the sum of all the values in a field (column)
COUNT - Counts the number of records (rows) where the field (column) matches a specified condition