SQL>
SQL> CREATE TABLE dept (
2 deptID INT NOT NULL PRIMARY KEY,
3 empID INT NOT NULL,
4 ClassID INT NOT NULL,
5 EnrolledOn DATE,
6 Grade INT);
Table created.
SQL>
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (1,1,1,DATE '2002-09-23',62);
1 row created.
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (2,1,2,DATE '2002-09-30',70);
1 row created.
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (3,2,3,DATE '2003-09-23',51);
1 row created.
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (4,2,5,DATE '2003-09-23',41);
1 row created.
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (5,2,6,DATE '2003-09-23',68);
1 row created.
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (6,3,4,DATE '2002-09-30',78);
1 row created.
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (7,3,7,DATE '2002-09-30',80);
1 row created.
SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (8,4,8,DATE '2002-09-20',70);
1 row created.
SQL>
SQL> CREATE TABLE empExam (
2 empID INT NOT NULL,
3 ExamID INT NOT NULL,
4 Mark INT,
5 Taken SMALLINT,
6 Comments VARCHAR(255),
7 CONSTRAINT PK_empExam PRIMARY KEY (empID, ExamID));
Table created.
SQL>
SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (1,1,55,1,'Satisfactory');
1 row created.
SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (1,2,73,1,'Good result');
1 row created.
SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (2,3,44,1,'Hard');
1 row created.
SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (2,5,39,0,'Simple');
1 row created.
SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken) VALUES (2,6,63,1);
1 row created.
SQL>
SQL> SELECT empID, Grade FROM dept e
2 WHERE Grade < ANY (
3 SELECT Mark/2 FROM empExam s
4 WHERE s.empID = e.empID);
no rows selected
SQL>
SQL> drop table dept;
Table dropped.
SQL> drop table empExam;
Table dropped.