pl/pgsql Debugger

or

pgAdmin Debugger

http://www.pgadmin.org/docs/1.8/debugger.html

Install

1. Edit postgresql.conf file (in folder C:\Program Files\PostgreSQL\9.3\data)

2. Add the debugging shared library to your shared_preload_libraries by removing the # 
     n.b you may have to edit the directory
 

1.  

3. In Postgres evoke the command CREATE EXTENSION pldbgapi 

4. Restart the services

Done