SQL Buffer
The field where SQL * Plus stores the most presently typed SQL commands or PL/SQL commands is known as the SQL Buffer. Command remains in the buffer until another command is entered. Therefore, if the similar command or block has to be edited or re-executed, it can be done without retyping the similar. A detailed list of SQL * Plus commands are dealt later.
Note: SQL * Plus commands are not stored in the SQL buffer and therefore may not be re-run.