Here's a brief review (ZDNet) of Interbase, PostgreSQL, and MySQL. http://www.zdnet.com/pcweek/stories/news/0,4153,2436153,00.html General consensus is, for high-read / low write, MySQL is fastest, but in a dynamic environment PostreSQL shines. Some caching issues with the current Intebase for Linux hampers performance, but that should be resolved as things evolve. Here's a thread from /. with some good discussion. http://slashdot.org/askslashdot/99/08/10/0416205.shtml