SQL Hints

FULL Hint
The FULL hint instructs the optimizer to perform a full table scan for the specified table

SELECT /*+ FULL(e) */ employee_id, last_name
  FROM hr.employees e 
  WHERE last_name LIKE :b1;

INDEX Hint

The INDEX hint instructs the optimizer to use an index scan for the specified table. You can use the INDEX hint for function-based, domain, B-tree, bitmap, and bitmap join indexes.


SELECT /*+ INDEX (employees emp_department_ix)*/ 
       employee_id, department_id 
  FROM employees 
  WHERE department_id > 50;

xplan as rule
/*+RULE */