REM must be the first non-blank character string in the line.
Examples
Examples of valid comments embedded in a SQL file follow:
REM This command file is used to create a
REM database. Edit it to fill in file names
REM and sizes, and invoke it from line mode.
REM
REM
CREATE DATABASE dbname ....
/* This is a SQL comment */ ...
...
;
REMARKs are recognized by SQL*Plus, as well as by line mode. They are used to put comments between SQL statements, while SQL comments (/*...*/) are used to place comments within statements.