I want to setup a sandbox environment to hone in on my pl/sql and database skills. I was thinking of downloading the full version of Oracle 11G and using SQL Developer. Se
ISTBC, but I believe you need a licence to run 11g Enterprise Edition, Standard Edition or Standard Edition One.
Express Edition however is free. It's exactly the same database, it just has some size limits that you're unlikely to hit whilst you're learning.
Oracle Database 11g Express Edition (Oracle Database XE) is an entry-level, small-footprint database based on the Oracle Database 11g Release 2 code base. It's free to develop, deploy, and distribute; fast to download; and simple to administer.
More info here:
http://www.oracle.com/technetwork/database/express-edition/overview/index.html