There are two ways to place comments into PL/SQL codes:

► SQL Statement Style: Starts you comment any where in the line but prefixed with '--'. The comment ends at the end of the line.

► C Language Style: Starts you comment any where in the line with '/*' and ends it with '*/' in the same line or some lines below.

Here is some example of PL/SQL comments:

BEGIN

-- This is a comment

/* To do:

Need to write some codes here

*/

END;