The theme of this paper is to report on the development of two graphical clients 
using
OpenMap™. The first client supports the native geometric data types of the
PostgreSQL DBMS. This development was exploratory in nature. Our main
goal was to develop a client that supports the spatial objects of PostGIS[2], the
spatial extension of PostgreSQL[3]. Both clients allow the user to issue SQL commands
to the DBMS using different JDBC extensions that support spatial data types. The
resulting data is displayed in OpenMap™. In both clients a layer was created capable
of converting the database types into the graphic objects required by the OpenMap™
framework.

The simple PostgreSQL client served as learning experience. It helped us understand
the nuances of both OpenMap™ and the non-standard spatial JDBC extension.
Obviously the development of the PostGIS client is of more value and of more
interest in the long term. To the best of our knowledge no queryable OpenMap™
client existed for PostgreSQL/PostGIS before this project. We feel that the ability 
to
send ad-hoc queries to PostgreSQL/PostGIS and display the results is a useful
contribution to the open source GIS community. From our own research perspective
the clients allows us to examine other issues, such security and authentication 
within
GIS. We must commend the quality of the open source products and the assistance
that we received from the developers of those products.