Nested Loop high low Unique Index Hash Join High High No Index Sort Merge High High No Unique Index + ORDER BY SELECT e.employee_id, e.first_name, e.salary, e.department_id, d.department_name FROM employees e, departments d WHERE e.department_id = d.department_id AND e.employee_id = 101; SELECT e.employee_id, e.first_name, e.salary, e.department_id, d.department_name FROM employees e, departments d WHERE d.department_id = e.department_id AND e.employee_id = 101; CREATE TABLE employees_tb AS SELECT * FROM employees; CREATE TABLE departments_tb AS SELECT * FROM departments; CREATE TABLE locations_tb AS SELECT * FROM locations; SELECT d.department_name, l.street_address FROM departments_tb d, locations_tb l WHERE d.location_id = l.location_id AND d.department_id = 20; SELECT e.employee_id, e.first_name, e.salary, e.department_id, d.department_name FROM employees e, departments d WHERE e.department_id = d.department_id AND e.manager_id = 100 ORDER BY 1; CREATE INDEX IN01 ON employees_tb(employee_id); CREATE INDEX IN02 ON employees_tb(manager_id); CREATE INDEX IN03 ON departments_tb(department_id); SELECT d.department_name, l.street_address FROM departments_tb d, locations_tb l WHERE d.location_id = l.location_id AND d.department_id = 20 ORDER BY d.department_name; DROP INDEX IN01; DROP INDEX IN02; DROP INDEX IN03; DROP TABLE employees_tb; DROP TABLE departments_tb; DROP TABLE locations_tb;