For all commandline application emacs can be used as an interface. You can open the shell mode and run the command line tool. Emacs will send the command you input to the command line tool and read and the display the output. Because you type your input to emacs you can manipulate your input using the emacs commands. Using this mode emacs can be used with the following oracle tools like*
There is a special sql-oracle mode that especially supports sqlplus. I worked with it long time ago. Today I did not find it in the documentation. I searched the web and but I found only the following link. Maybe you can find more when searching the emacs documents. There are other sql modes for emacs. This page contains a reference to the link found by @Jack Douglas too.
A lot of people don't like emacs because they think that it is a complex tool.