set serveroutput on

When we execute PL/SQL program  into Oracle engine so we always required to get output result and display
into the screen otherwise result can't be display.

Whenever we connect Oracle SQL (PL/SQL) at that time you must have to write the "set serveroutput on" command.


SQL> set serveroutput on

PL/SQL Comment you can write single line or either multiple line,

1.Multi-line comments and
2.Single line comments
SQL>-- Single Line Comment

SQL>/*  Multiline Comment line 1
Multiline Comment line2    */1