[no subject]

    SELECT * FROM sources INTO src WHERE source_id = $1;

SELECT * is generally something to avoid. You end up shoving around more
data than needed. Granted, in this case it's only getting shoved down
into plpgsql, but it's still extra work for the server.

Also, the commentary about how MySQL is faster isn't very clear. Are you
using MySQL as some kind of result cache? When you get to running actual
concurrent access on the website, you could well find yourself very
disappointed with the performance of MyISAM and it's table-level
locking. There's probably also some gains to be had on the PostgreSQL
performance.
-- 
Jim C. Nasby, Sr. Engineering Consultant      jnasby(at)pervasive(dot)com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461