Over the years, I’ve seen people ask questions on where they can access a demo Oracle database so that they can practice and learn SQL or PL/SQL. Until today, I never knew of any available Oracle testbed for public consumption. Now, Oracle Corp has provided us with LiveSQL.oracle.com and the only thing you need to access the site is a free OTN account.
Live SQL lets you access a SQL Worksheet where you can enter SQL and PL/SQL commands. You also have read-only access to the HR and SH sample schemas.
I’ve been working on tuning some SQL statements in a newly upgraded database, from Oracle 220.127.116.11 to 18.104.22.168. As I typically do, I like to use SQL Developer to see the Explain Plan. I was surprised to see some gray text in the Explain Plan output, which you can see below.