May I suggest the recent discussion over the dreaded NL issue ... I had somesimilar ideas.
http://www.postgresql-archive.org/OLAP-reporting-queries-fall-into-nested-loops-over-seq-scans-or-other-horrible-planner-choices-td5990160.html
This could be massively useful and a huge leap in the industry.
--Sent from: http://www.postgresql-archive.org/PostgreSQL-performance-f2050081.html