For the first time, I'm using MySQL.
[rant]
It's also kinda frustrating too though. I tried to figure out how to use the CREATE TABLE syntax from the MySQL documentation but I gave up and cheated and used PHPMyAdmin. I create a table that looks about right, and then as I start loading data I tweak it a bit, until I get the design I want. It's pretty annoying sometimes, because for one of my tables I had to splice out one of the values I took for granted (it was "category") because there could be multiple assignments for just one entry. Then, as I was designing the Category Tree table (that maps the relationship between categories) I found out that I had to, once again, split the table into category hierarchy (the hierarchy would be redesigned to do preordered tree traversal which I barely understand) and subcategories (don't ask). So now I have three tables on categories and I'm going to have to make querys for all of them and learn new types of algorithms and it's all gotten so complicated. So much for the tweak and run method.
[/rant]
When you have to accomodate for some novel sort of datatype inside a relational database, how do you go about designing the table?