On Fri, 26 Sep 2008, Mike Miller wrote: > We have a lot of data -- apparently about 9,000 tables in an RDBMS. It's > in Oracle now. As a fan of open source solutions, I would prefer to use > MySQL or other open source RDBMS, but at what cost? Before I even > consider moving data to MySQL from Oracle, I want to know what Oracle can > do that MySQL (or other FOSS product) cannot do. Have any of you studied > this or do you know of any reasonably serious comparative research or > reviews? Thanks. We use Postgresql at work, and it works great. And it'd probably be easier to move from Oracle to Postgres than from Oracle to MySql- of all the open source databases, Postgres is the most like Oracle. It also scales well. We don't have thousands of tables, but we do have hundreds- several of which are at least medium-sized (pushing 100G per table). And I know people who have 10's of TB in Postgres databases. It also scales in terms of query complexity- we haven't noticed any problems with queries until you start getting 60-100 tables in the same join. So, in your situation, I'd recommend Postgresql rather strongly. Brian