 |
 |
|
|
|
|
|
|
 |
| |
|
|
|
You will find this Glossary of Terms useful if you are just getting started.
If you are familiar with Spreadsheets then you should think of a Worksheet as a Table in a Database.
The collection of Worksheets is like the Tables in a Database.
Data in Tables in a Database can be manipulated with a language called SQL, or 'Structured Query Language'.
This is pronounced either 'See-Quel' or the letters 'S-Q-L'.
The table shown below defines the meaning of individual Terms.
An Overview
As an overview, we can say that a Database contains Tables and Relationships.
Each Table contains Rows of data laid out in Columns.
For example, a Database for Facebook would contain a Members Table and a Friends Table.
The Members Table would contain a Row for each Member. A Row would contain a number of Columns, with one Column for each item of information, such as Date of Birth.
We link Tables to express the Relationships between them. For example, in our Facebook example, we link Members and Friends to express the Relationship that says 'A Member can have many Friends', or more exaxctly, 'One Member can be linked to many Rows in the Friends Table'.
|
|
|
|
|
|
| |
|
|
|
|
 |
| |
 Column |
A Column is one item of data, such as a Date of Birth. |
| Database |
A Database consists of a number of Tables, with Relationships between them.
For instance, a Database for Facebook would contain a Table for Members and another Table for Members Friends.
|
| Field |
A Field is another word for a Column, in other words, one item of data, such as a Date of Birth.
|
| Relationship |
A Relationship defines how two (and only two) Tables are related.
For example, in a Facebook Database, a Members Table would be related to a Friends Table by a Relationship that would say,in English,
'A Member can have zero, one or many Friends'.
|
| Row |
A Row is a set of data in a Table. For example, in a Facebook Members Table, a Row could contain Name, Date of Birth, Gender and Address. |
| Table |
A Table contains data which is stored in Rows and Columns.
|
|
|
|
|
|
|
|
