When you work with Oracle database, you work with a complete set of rows returned from an SELECT statement. However the application in some cases cannot work effectively with the entire result set, therefore, the database server needs to provide a mechanism for the application to work with one row or a subset of the result set at a time. As the result, Oracle created PL/SQL cursor to provide these extensions.
The PL/SQL loops are used to repeat the execution of one or more statements for specified number of times. These are also known as iterative control statements.
