SELECT familia, grup FROM student a, grup b WHERE n_stud IN;
SELECT n_stud FROM ocenki WHERE n_predm=(идентификатор предмета) AND ocenka< 3 );
AND a.n_grup==b.n_grup ORDER BY grup, familia

SELECT a.familia, b.grup FROM student a, grup b WHERE a.n_stud IN;
(SELECT n_stud FROM ocenki WHERE n_predm= 11  AND ocenka<"3");
AND a.n_group==b.n_grup ORDER BY grup, familia

SELECT DISTINCT a.familia, b.grup, c.predm FROM student a, grup b, predmet c, ocenki d;
INTO TABLE c:\tmp.dbf WHERE a.n_stud IN;
(SELECT n_stud FROM ocenki WHERE ocenka< 3 );
AND a.n_group==b.n_grup AND c.n_predm==d.n_predm ORDER BY grup, familia

SELECT TMP.Predm, TMP.Grup, TMP.Familia;
    FROM TMP;
    GROUP BY TMP.Predm, TMP.Grup, TMP.Familia;
    ORDER BY TMP.Predm, TMP.Grup, TMP.Familia;
    INTO CURSOR SYS( 2015 )
DO (_GENXTAB) WITH 'Query',,,,,,,,,.t.
BROWSE NOMODIFY