CREATE TABLE DEPT 
       (DEPTNO NUMBER(2) CONSTRAINT PK_DEPT PRIMARY KEY, 
        DNAME VARCHAR2(14) , 
        LOC VARCHAR2(13) ) 

CREATE TABLE EMP 
       (EMPNO NUMBER(4) CONSTRAINT PK_EMP PRIMARY KEY, 
        ENAME VARCHAR2(10), 
        JOB VARCHAR2(9), 
        MGR NUMBER(4), 
        HIREDATE DATE, 
        SAL NUMBER(7,2), 
        COMM NUMBER(7,2), 
        DEPTNO NUMBER(2) CONSTRAINT FK_DEPTNO REFERENCES DEPT)

begin 
INSERT INTO DEPT VALUES 
        (10,'ACCOUNTING','NEW YORK'); 
INSERT INTO DEPT VALUES (20,'RESEARCH','DALLAS'); 
INSERT INTO DEPT VALUES 
        (30,'SALES','CHICAGO'); 
INSERT INTO DEPT VALUES 
        (40,'OPERATIONS','BOSTON'); 
INSERT INTO EMP VALUES 
(7369,'SMITH','CLERK',7902,to_date('17-12-1980','dd-mm-yyyy'),800,NULL,20); 
INSERT INTO EMP VALUES 
(7499,'ALLEN','SALESMAN',7698,to_date('20-2-1981','dd-mm-yyyy'),1600,300,30); 
INSERT INTO EMP VALUES 
(7521,'WARD','SALESMAN',7698,to_date('22-2-1981','dd-mm-yyyy'),1250,500,30); 
INSERT INTO EMP VALUES 
(7566,'JONES','MANAGER',7839,to_date('2-4-1981','dd-mm-yyyy'),2975,NULL,20); 
INSERT INTO EMP VALUES 
(7654,'MARTIN','SALESMAN',7698,to_date('28-9-1981','dd-mm-yyyy'),1250,1400,30); 
INSERT INTO EMP VALUES 
(7698,'BLAKE','MANAGER',7839,to_date('1-5-1981','dd-mm-yyyy'),2850,NULL,30); 
INSERT INTO EMP VALUES 
(7782,'CLARK','MANAGER',7839,to_date('9-6-1981','dd-mm-yyyy'),2450,NULL,10); 
INSERT INTO EMP VALUES 
(7788,'SCOTT','ANALYST',7566,to_date('13-JUL-87','dd-mm-rr')-85,3000,NULL,20); 
INSERT INTO EMP VALUES 
(7839,'KING','PRESIDENT',NULL,to_date('17-11-1981','dd-mm-yyyy'),5000,NULL,10); 
INSERT INTO EMP VALUES 
(7844,'TURNER','SALESMAN',7698,to_date('8-9-1981','dd-mm-yyyy'),1500,0,30); 
INSERT INTO EMP VALUES 
(7876,'ADAMS','CLERK',7788,to_date('13-JUL-87', 'dd-mm-rr')-51,1100,NULL,20); 
INSERT INTO EMP VALUES 
(7900,'JAMES','CLERK',7698,to_date('3-12-1981','dd-mm-yyyy'),950,NULL,30); 
INSERT INTO EMP VALUES 
(7902,'FORD','ANALYST',7566,to_date('3-12-1981','dd-mm-yyyy'),3000,NULL,20); 
INSERT INTO EMP VALUES 
(7934,'MILLER','CLERK',7782,to_date('23-1-1982','dd-mm-yyyy'),1300,NULL,10); 
end; 

select * from dept join emp using(deptno)

explain plan for select * from dept join emp using(deptno)

select * from table(dbms_xplan.display)