1.SELECT ename
FROM employees
WHERE eno IN
(SELECT eno
FROM working
GROUP BY eno
HAVING COUNT (*)=
(SELECT COUNT (*)
FROM projects));
This will return : Employee name who is working for all projects.
(ii)
SELECT pname
FROM projects
WHERE pno IN
(SELECT pno
FROM projects
MINUS
SELECT DISTINCT pno
FROM working);
This will return : Project name for which no employee is working.