Different Types of SQL-01

Inline Views:

        SELECT ed.first_name, ed.department_name
FROM   (SELECT e.first_name, d.department_name
        FROM   employees e, departments d
        WHERE  d.department_id = e.department_id) ed
ORDER BY ed.first_name;

WITH Clause:

WITH emp_dept AS (
  SELECT e.first_name, d.department_name
  FROM   employees e, departments d
  WHERE  d.department_id = e.department_id
)
SELECT ed.first_name, ed.department_name
FROM   emp_dept ed
ORDER BY ed.first_name;

Views:

CREATE OR REPLACE VIEW emp_dept_join_v AS
  SELECT e.first_name, d.department_name
  FROM   employees e, departments d
  WHERE  d.department_id = e.department_id;
 
SELECT ed.first_name, ed.department_name
FROM   emp_dept_join_v ed
ORDER BY ed.first_name;