[Vince]

There are multiple built in function to convert date and time. A Unix timestamp saves both date and time in one normal integer variable. I think I've linked these article to you before;
http://dev.mysql.com/doc/refman/5.0/..._from-unixtime
http://dev.mysql.com/doc/refman/5.0/...on_date-format

I suggest you take a long look at these examples, because I can't really explain it better than they already did.