Table Template Design

MySQL provides a number of data types for representing the attributes of the object. The previous list of attributes will then be modelled in the form of columns, as shown in the following table:

Data	Column name	Data type
Unique identification number	id	UNSIGNED SMALLINT, Auto-incremented
Title	titre	VARCHAR, maximum 128 characters
Author name	auteur	VARCHAR, maximum 32 characters
Short introduction	short_intro	TEXT
Description	long_intro	TEXT
Body	corps	LONGTEXT
Name of an image file	image	VARCHAR, maximum 128 characters
Topic	theme	ENUM('news','music','cinema')
Category	type	ENUM('interview','story','review')
Date	date	DATE
Yes/No type variable	affichage	ENUM('yes','no')

To help you understand this table better, let's examine the various types of data that are used:

• SMALLINT represents an integer between 0 and 65 535 (the UNSIGNED only permits positive numbers).
  
  
By comparison with the INT type, SMALLINT contains smaller numbers and consequently takes up less memory space. It is nevertheless sufficient for our article counter.


• VARCHAR contains text strings of variable lengths, whose maximum number of characters is known.
  
  
• TEXT is a data type for text fields containing a maximum of 64KB of text. As for LONGTEXT, it can store up to 4GB of text!
  
  
These types are useful to store a content of which you do not know the size.


• ENUM is used to define a predefined list of values accepted in a column.
  
  
All attempts at inserting an unknown value will be rejected by the MySQL server. The first two ENUM columns listed in the table allow only topics and categories as values; they can be customised. The last ENUM column acts as if it were a boolean type, accepting only one of the two values 'yes/no'.