list all employees who is younger than Joe : Correlated Subquery « Query Select « Oracle PL/SQL Tutorial






  1. Oracle PL/SQL Tutorial
  2. Query Select
  3. Correlated Subquery
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>
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>
SQL> select ename, init, bdate
  2  from   employees
  3  where  bdate > (select bdate
  4                  from   employees
  5                  where  ename = 'JONES');

no rows selected

SQL>
SQL> drop table employees;

Table dropped.








2.37.Correlated Subquery
2.37.1.Writing Correlated Subqueries
2.37.2.Using EXISTS and NOT EXISTS with a Correlated Subquery
2.37.3.A correlated subquery: the subquery references a column from a table referred to in the parent statement.
2.37.4.The subquery returning the literal value 1
2.37.5.Using NOT EXISTS with a Correlated Subquery
2.37.6.list all employees who is younger than Joe
2.37.7.List all employees who attended XML course and Java course
2.37.8.Extract a Subset of the Results
2.37.9.How Many Products By Department with correlated subqueries 1
2.37.10.How Many Products By Department with correlated subqueries 2
2.37.11.Correlated subquery using the EXISTS operator