SQL

displaying different entities from different tables at once

SELECT E.first_name NAME,D.department_name DNAME
FROM employees E NATURAL JOIN departments D;

FIRST_NAME DNAME
---------- ------
MILLER     DEPT 1
JOHN       DEPT 1
MARTIN     DEPT 2
EDWIN      DEPT 2

displaying different entities from different tables at once

SELECT E.first_name NAME,D.department_name DNAME
FROM employees E JOIN departments D
ON (E.department_id = D.department_id);