I am by no means a database design guru, the table contains info about clients, each row is a different client, each column a unique attribute of the client. I obviously could break the table into many tables, but then I woud have 1 to 1 relationships abounding, and lots of JOINS in my SQL.

I sort of assumed that KISS was wise, and large and simple was better than small and complex. But I don't really know which is better.

Are there any rules-of-thumb for how many columns tables should have?