Binary data include pictures and sound waves. Many web hosting companies do not allow the use of binary data in a database because they slow down the speed of searches and overall performance of the database. Instead of putting this type of data in the table, include links to the picture or sound wave.
Blobs and text types can be used to store large amounts of text. If this data is static, it may be better to store it in a text file, or xml file instead of in the database.
A set type specifies all of the allowed data.
For example, a field defined as
language SET('English', 'Spanish')
can have any of these values: '', 'English', 'Spanish','English,Spanish'
A set can have a maximum of 64 different members.
The enum type can have one of a list of values. For example a filed defined as gender
gender ENUM('M', 'F')
Note: When using set and enum types you will probably create the form using either a list box or option buttons for enum, and check boxes for sets.
The name of the field is followed by the type. You can then include any of the following NOT NULL, NULL or DEFAULT ="value"
Example: state CHAR(2) NOT NULL DEFAULT="MD"