Re: more about using sets

[Michael T. Babcock]

Luc Foisy wrote:

What exactly is wrong about using ENUM's?

Changing them will kill you unless you're _very_ careful.

Using them is usually unnecessary as you could've used an ID value pointing to another table of values. That table can then be added to with no risk to your existing queries. As a contrived example:

Employee
----------
ID ... primary key
Gender enum('male','female')
vs.
GenderID tinyint

Gender
------
ID tiny int ... primary key
Name varchar(10)

INSERT into Gender(Name) values ('male'),('female');

Later, you might need:
INSERT into Gender(Name) values ('unknown');

--
Michael T. Babcock
C.T.O., FibreSpeed Ltd. SQL
http://www.fibrespeed.net/~mbabcock



---------------------------------------------------------------------
Before posting, please check:
http://www.mysql.com/manual.php (the manual)
http://lists.mysql.com/ (the list archive)

To request this thread, e-mail <[EMAIL PROTECTED]>
To unsubscribe, e-mail <[EMAIL PROTECTED]>
Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php