There are two key advantages to PostgreSQL over MySQL when it comes to bioinformatics: 1) PostgreSQL is a true object-relational DBMS 2) PostgreSQL was designed on the premise of extensibility (3rd Manifesto, H.Downs) Essentially, PostgreSQL was designed to be adaptable (user defined data types/blades) and well-suited for complex queries. To say that MySQL is inherently faster is misleading. A good resource for these types of issues/problems would be the consulting group out of Berkekely (ex-INGRES folks): i think it is http://www.varlena.com . i'm currently using postgresql and neural nets on secondary structure prediction of proteins. we are using Joone as the 'OO glue' for distributed processing. lon @ efcodd.org