Scott Selikoff wrote:Good question, do you need a JDBC/RDBMS foundation to start in PostGIS?
Haven't seen the PostGIS book yet, but you don't need any Java at all to use PostGIS.
PostGIS is an add-on to the PostgreSQL RDBMS and provides additional data-types and functions to support spatial data. You define table columnss with spatial data types, index them, and apply spatial functions to them via SQL (or PGPLSQL).
If you don't know anything about databases, then you probably won't know how to take advantage of PostGIS either. But maybe the PostGIS book will help you get started in the context of examples using spatial data.
Because it's an RDBMS, you can use pretty much any language to talk to the DB from external applications e.g. Java, Python, etc. Also, there are lots of GIS tools that talk directly to PostGIS/PostgreSQL data sources (some of them Java-based such as GeoServer), as well as various standard XML formats and web services, so you don't necessarily need to code the DB interaction anyway.
For a wider introduction to open source GIS using PostGIS and other tools, try Dekstop GIS by Gary Sherman.