On Thu, 7 Apr 2005, Brent Baisley wrote: Thank you Brent.
> As mentioned in the manual you specified, there are limits to how many > items you can have in a set, among other issues. My biggest issue > against using sets is that you need alter the table structure whenever > you want to change the set. Usually I would want the user to be able > to add, modify or delete list items. You do NOT want a user being able > to alter the table structure. > The three table layout gives you basically unlimited scalability, > easier and quicker modification, dynamic sorting, more flexible > searching and no character restrictions. I can see the unlimited scalability, quicker modification, and no character restrictions. "Dynamic sorting"? Do you mean there's a sort that the three table layout can do that can't be done with the set type? Or a search? I'm sorry to be so dense, but can you give me an example? Thank you again. Marilyn Davis > > > On Apr 7, 2005, at 5:20 PM, Marilyn Davis wrote: > > > Hi MySQL people. > > > > I'm trying to understand the pros and cons of the "set" column type. > > > > Here is an excerpt from the article: > > > > http://dev.mysql.com/tech-resources/articles/mysql-set-datatype.html > > > > > > Why You Shouldn't Use SET > > > > "Third, using a set means your data is not normalized. In our above > > example, we are tracking a person's interests for a hypothetical > > dating site. In a normalized schema, there should be three tables: one > > for the person, one for all possible interests, and one that links a > > person to their particular interests." > > > > The "above example" is: > > > > CREATE TABLE set_test( > > rowid INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY, > > myset SET('Travel','Sports','Dancing','Fine Dining') > > ); > > > > I guess I'm not understanding the point here. What practical > > advantage is there to creating three tables instead of using a set > > column type? > > > > Thank you for any help. > > > > Marilyn Davis > > > > > > > > > > -- > > MySQL General Mailing List > > For list archives: http://lists.mysql.com/mysql > > To unsubscribe: > > http://lists.mysql.com/[EMAIL PROTECTED] > > > > > -- -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
