Differences between SQL Plus and "regular" SQL?
- Yes. SQL*Plus is a client tool. SQL is what actually gets run on the server.
- Documentation for SQL*Plus is here and here A lot of the 'extensions' are presentation related (eg how wide your screen is)
- Not really in SQL*Plus. If you use SQL*Plus for long, you'll soon find out you really NEED to be able to change the default linesize, page size, column sizes, number formatting...
- Personally, while it is good to know how to do things in SQL*Plus, one of the GUI client tools can be a lot easier. Personally I use SQL Squirrel for most stuff, and my favourite editor and SQL*Plus for PL/SQL program development.