It's not free, but Applixware works with postgresql via postodbc. I
have some detailed setup information (Thanks Tom!) at:
http://www.radix.net/~cobrien/applix
There is a query tool (Data) that lets you set up queries
without using sql, and also update tables. Once queries are
set up, you can import the queries either into documents or
spreadsheets. Applixware is $99 for Linux, runs on intel, alpha,
and powerpc. Pretty good support through the mailing list.
More at http://linux.applix.com. I don't work for them, just
a happy user.
Drop me a line if you have any questions.
--cary
Cary O'Brien
cobrien@radix.net