Implicit VS explicit cursor

1. PL/SQL employs an implicit cursor for each UPDATE, DELETE, or INSERT statement you execute in a program. You cannot, execute these statements within an explicit cursor, even if you want to.
2. You have a choice between using an implicit or explicit cursor only when you execute a single-row SELECT statement (a SELECT that returns only one row).
3. When SELECT returns more than one row you may or may not have to use explicit cursor depends on usecase.
4. If you use an implicit cursor, Oracle performs the open, fetches, and close for you automatically; these actions are outside of your programmatic control.