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.
There is a special sql-oracle mode that pecially supports sqlplus. I worked with hin long time ago but 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 emcas documents.
A lot of people don't like emacs because they think that it is a complex tool.