Join using and join on
SQL> SQL> create table emp 2 ( empno NUMBER(4) constraint E_PK primary key 3 , ename VARCHAR2(8) 4 , init VARCHAR2(5) 5 , job VARCHAR2(8) 6 , mgr NUMBER(4) 7 , bdate DATE 8 , sal NUMBER(6,2) 9 , comm NUMBER(6,2) 10 , deptno NUMBER(2) default 10 11 ) ; Table created. SQL> insert into emp values(1,'Tom','N', 'TRAINER', 13,date '1965-12-17', 800 , NULL, 20); 1 row created. SQL> insert into emp values(2,'Jack','JAM', 'Tester',6,date '1961-02-20', 1600, 300, 30); 1 row created. SQL> insert into emp values(3,'Wil','TF' , 'Tester',6,date '1962-02-22', 1250, 500, 30); 1 row created. SQL> insert into emp values(4,'Jane','JM', 'Designer', 9,date '1967-04-02', 2975, NULL, 20); 1 row created. SQL> insert into emp values(5,'Mary','P', 'Tester',6,date '1956-09-28', 1250, 1400, 30); 1 row created. SQL> insert into emp values(6,'Black','R', 'Designer', 9,date '1963-11-01', 2850, NULL, 30); 1 row created. SQL> insert into emp values(7,'Chris','AB', 'Designer', 9,date '1965-06-09', 2450, NULL, 10); 1 row created. SQL> insert into emp values(8,'Smart','SCJ', 'TRAINER', 4,date '1959-11-26', 3000, NULL, 20); 1 row created. SQL> insert into emp values(9,'Peter','CC', 'Designer',NULL,date '1952-11-17', 5000, NULL, 10); 1 row created. SQL> insert into emp values(10,'Take','JJ', 'Tester',6,date '1968-09-28', 1500, 0, 30); 1 row created. SQL> insert into emp values(11,'Ana','AA', 'TRAINER', 8,date '1966-12-30', 1100, NULL, 20); 1 row created. SQL> insert into emp values(12,'Jane','R', 'Manager', 6,date '1969-12-03', 800 , NULL, 30); 1 row created. SQL> insert into emp values(13,'Fake','MG', 'TRAINER', 4,date '1959-02-13', 3000, NULL, 20); 1 row created. SQL> insert into emp values(14,'Mike','TJA','Manager', 7,date '1962-01-23', 1300, NULL, 10); 1 row created. SQL> SQL> create table departments 2 ( deptno NUMBER(2) constraint D_PK primary key 3 , dname VARCHAR2(10) 4 , location VARCHAR2(8) 5 , mgr NUMBER(4) 6 ) ; Table created. SQL> SQL> insert into departments values (10,'ACCOUNTING','NEW YORK',7); 1 row created. SQL> insert into departments values (20,'TRAINING', 'DALLAS', 4); 1 row created. SQL> insert into departments values (30,'SALES', 'CHICAGO', 6); 1 row created. SQL> insert into departments values (40,'HR', 'BOSTON', 9); 1 row created. SQL> SQL> select e.empno 2 , e.ENAME 3 , e.init 4 , d.dname 5 , d.location 6 , m.ENAME as Designer 7 from emp e 8 join 9 departments d using (deptno) 10 join 11 emp m on (m.empno = d.mgr); EMPNO ENAME INIT DNAME LOCATION DESIGNER ---------- -------- ----- ---------- -------- -------- 1 Tom N TRAINING DALLAS Jane 2 Jack JAM SALES CHICAGO Black 3 Wil TF SALES CHICAGO Black 4 Jane JM TRAINING DALLAS Jane 5 Mary P SALES CHICAGO Black 6 Black R SALES CHICAGO Black 7 Chris AB ACCOUNTING NEW YORK Chris 8 Smart SCJ TRAINING DALLAS Jane 9 Peter CC ACCOUNTING NEW YORK Chris 10 Take JJ SALES CHICAGO Black 11 Ana AA TRAINING DALLAS Jane 12 Jane R SALES CHICAGO Black 13 Fake MG TRAINING DALLAS Jane 14 Mike TJA ACCOUNTING NEW YORK Chris 14 rows selected. SQL> drop table emp; Table dropped. SQL> drop table departments; Table dropped. SQL>