I've been reading a lot of fuss over Oracle's databases and how the largest of large corporations use them. What exactly does Oracle have that MySQL have?
I don't use Oracle much, but the main difference is in the enterprise level features. Until 5.0, MySQL did not do stored procs, transactions, etc.... MySQL, to my knowledge, also does not natively allow for live back ups. In addition there are analytical tools that the big boys have that others do not. That being said, MySQL in its current version is highly scaleable and very good. If you are AT&T, you'll still want to use Oracle or MS SQL or DB2. If you are running a few forums sites, MySQL is just fine (and 100% cheaper). Here are some links that might be useful. Comparison of several DBs Comparison of MS SQL Server 2000 and MySQL 4.1 Oracle, MS SQL, MySQL Comparison
oracle has a big company name, they are in the top 3 largest software companies in the world. mySQL started from freeware and now they are trying to make some money on it. Otherwise a database is a database. I use oracle daily but that's because it's the only database that truly supports spatial data processing