Mega Code Archive
Query a view with subquery
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SQL>
SQL> create table employees(
2 empno NUMBER(4)
3 , ename VARCHAR2(8)
4 , init VARCHAR2(5)
5 , job VARCHAR2(8)
6 , mgr NUMBER(4)
7 , bdate DATE
8 , msal NUMBER(6,2)
9 , comm NUMBER(6,2)
10 , deptno NUMBER(2) ) ;
Table created.
SQL>
SQL> insert into employees values(1,'Jason', 'N', 'TRAINER', 2, date '1965-12-18', 800 , NULL, 10);
1 row created.
SQL> insert into employees values(2,'Jerry', 'J', 'SALESREP',3, date '1966-11-19', 1600, 300, 10);
1 row created.
SQL> insert into employees values(3,'Jord', 'T' , 'SALESREP',4, date '1967-10-21', 1700, 500, 20);
1 row created.
SQL> insert into employees values(4,'Mary', 'J', 'MANAGER', 5, date '1968-09-22', 1800, NULL, 20);
1 row created.
SQL> insert into employees values(5,'Joe', 'P', 'SALESREP',6, date '1969-08-23', 1900, 1400, 30);
1 row created.
SQL> insert into employees values(6,'Black', 'R', 'MANAGER', 7, date '1970-07-24', 2000, NULL, 30);
1 row created.
SQL> insert into employees values(7,'Red', 'A', 'MANAGER', 8, date '1971-06-25', 2100, NULL, 40);
1 row created.
SQL> insert into employees values(8,'White', 'S', 'TRAINER', 9, date '1972-05-26', 2200, NULL, 40);
1 row created.
SQL> insert into employees values(9,'Yellow', 'C', 'DIRECTOR',10, date '1973-04-27', 2300, NULL, 20);
1 row created.
SQL> insert into employees values(10,'Pink', 'J', 'SALESREP',null,date '1974-03-28', 2400, 0, 30);
1 row created.
SQL>
SQL> create table registrations
2 ( attendee NUMBER(4)
3 , course VARCHAR2(6)
4 , begindate DATE
5 , evaluation NUMBER(1)) ;
Table created.
SQL>
SQL> insert into registrations values (1, 'SQL',date '1999-04-12',4 );
1 row created.
SQL> insert into registrations values (2, 'SQL',date '1999-12-13',NULL);
1 row created.
SQL> insert into registrations values (3, 'SQL',date '1999-12-13',NULL);
1 row created.
SQL> insert into registrations values (4, 'OAU',date '1999-08-10',4 );
1 row created.
SQL> insert into registrations values (5, 'OAU',date '2000-09-27',5 );
1 row created.
SQL> insert into registrations values (6, 'JAV',date '1999-12-13',2 );
1 row created.
SQL> insert into registrations values (7, 'JAV',date '2000-02-01',4 );
1 row created.
SQL> insert into registrations values (8, 'JAV',date '2000-02-01',5 );
1 row created.
SQL> insert into registrations values (9, 'XML',date '2000-02-03',4 );
1 row created.
SQL> insert into registrations values (10,'XML',date '2000-02-03',5 );
1 row created.
SQL> insert into registrations values (1, 'PLS',date '2000-09-11',NULL);
1 row created.
SQL> insert into registrations values (2, 'PLS',date '2000-09-11',NULL);
1 row created.
SQL> insert into registrations values (3, 'PLS',date '2000-09-11',NULL);
1 row created.
SQL>
SQL> create table courses
2 ( code VARCHAR2(6)
3 , description VARCHAR2(30)
4 , category CHAR(3)
5 , duration NUMBER(2)) ;
Table created.
SQL>
SQL> insert into courses values('SQL','SQL course', 'GEN',4);
1 row created.
SQL> insert into courses values('OAU','Oracle course', 'GEN',1);
1 row created.
SQL> insert into courses values('JAV','Java course', 'BLD',4);
1 row created.
SQL> insert into courses values('PLS','PL/SQL course', 'BLD',1);
1 row created.
SQL> insert into courses values('XML','XML course', 'BLD',2);
1 row created.
SQL> insert into courses values('ERM','ERM course', 'DSG',3);
1 row created.
SQL> insert into courses values('PMT','UML course', 'DSG',1);
1 row created.
SQL> insert into courses values('RSD','C# course', 'DSG',2);
1 row created.
SQL> insert into courses values('PRO','C++ course', 'DSG',5);
1 row created.
SQL> insert into courses values('GEN','GWT course', 'DSG',4);
1 row created.
SQL>
SQL> create or replace view course_days as
2 select e.empno
3 , e.ename
4 , sum(c.duration) as days
5 from registrations r
6 join courses c on (c.code = r.course)
7 join employees e on (e.empno = r.attendee)
8 group by e.empno
9 , e.ename;
View created.
SQL> select *
2 from course_days
3 where days > (select avg(days)
4 from course_days);
EMPNO last_name DAYS
------ -------------------- ------
7 Red 4
2 Jerry 5
6 Black 4
1 Jason 5
3 Jord 5
8 White 4
6 rows selected.
SQL>
SQL> drop table registrations;
Table dropped.
SQL>
SQL> drop table courses;
Table dropped.
SQL>
SQL> drop table employees;
Table dropped.
SQL>
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