It can handle ODBC/JDBC/MySQL/Adabas/Dbase thos are the main choices. I have not used Postgres.
Paradox on windows was brilliant. I had everything in that up to the point of switching to Linux 6-8 months ago.
OO 1.1. and Mysql work very well together.
Another thing for you to try Knoda that connects to Postgres.
Another thing for you to try :- http://www.ems-hitech.com/pgmanager/
I use the MySQLManager from EMS and it is a brilliant report-generator to many formats, perhaps their Postgres Manager is for you the solution?