Structure of PL/SQL Statements

All PL/SQL functions and procedures, including packaged procedures and anonymous blocks follow the following basic layout:

Structure:

 PROCEDURE procedure (
    parameter1 datatype [DEFAULT default_value1 ],
    parameter2 datatype [DEFAULT default_value2 ] [,...]) IS

 DECLARE
 /* declarations */
   
 BEGIN
 /* executable code */

 EXCEPTION
 /* error handling */

 END;
 /

or for a function:

   FUNCTION function RETURN datatype IS
   DECLARE  /* declarations */
   BEGIN    /* executable code */
  [RETURN value]
   EXCEPTION /* error handling */
   END;
   /

To create a procedure:

CREATE OR REPLACE PROCEDURE procedure IS
 ...
 END procedure;
 /

Or a flat file SQL script can contain simply:

   BEGIN
   /* executable code */

   EXCEPTION
   /* error handling */

   END;

This is known as an 'anonymous block'