--SA SE SCRIE O CERE SQL, CARE FACE O LISTA CU TOTI ANGAJATII CARE NU AU PRIMIT COMISION DAR AU VENIT IN FIRMA INAINTEA SEFULUI DIRECT:
--den_dep_subaltern	 nume_sub		data_ang_sub	nume_sef	data_ang_sef

SELECT
	d1.dname "DEN_DEP_SUB",
	e1.ename "NUME_SUB",
	e1.hiredate "DATA_ANG_SUB",
	e2.ename "NUME_SEF",
	e2.hiredate "DATA_ANG_SEF"
FROM
	emp e1,
	emp e2,
	dept d1
WHERE
	d1.deptno = e1.deptno AND
	e1.mgr = e2.empno AND
	(e1.comm = 0 OR e1.comm IS NULL) AND
	e1.hiredate < e2.hiredate;
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SELECT
	d1.dname "DEN_DEP_SUB",
	e1.ename "NUME_SUB",
	e1.hiredate "DATA_ANG_SUB",
	e2.ename "NUME_SEF",
	e2.hiredate "DATA_ANG_SEF"
FROM
	emp e1 natural join dept d1, emp e2
WHERE
	e1.mgr = e2.empno AND
	e1.hiredate < e2.hiredate  AND
	(e1.comm is NULL or e1.comm = 0);
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SELECT
	d1.dname "DEN_DEP_SUB",
	e1.ename "NUME_SUB",
	e1.hiredate "DATA_ANG_SUB",
	e2.ename "NUME_SEF",
	e2.hiredate "DATA_ANG_SEF"
FROM
	dept d1,
	emp e1 FULL OUTER JOIN emp e2
		ON e1.mgr = e2.empno
WHERE
	d1.deptno = e1.deptno AND
	(e1.comm = 0 OR e1.comm IS NULL) AND
	e1.hiredate < e2.hiredate;
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