Setup Step 1

CREATE TABLE emp2 AS  
SELECT * 
FROM scott.emp

Setup Step 2

CREATE TABLE emp AS  
SELECT * 
FROM scott.emp

Modify some records

UPDATE emp2 
SET ename='SMITE' 
WHERE empno=7369

UPDATE emp2 
SET job='SALESGUY' 
WHERE empno=7499

UPDATE emp2 
SET mgr=7788 
WHERE empno=7521

UPDATE emp2 
SET sal=1750 
WHERE empno=7654

UPDATE emp2 
SET comm=1000 
WHERE empno=7698

DELETE FROM emp2 
WHERE empno=7902

DELETE FROM emp 
WHERE empno=7788

Show the differences

WITH x AS ( 
SELECT  empno, ename, job, mgr, sal, comm, 'EMP' tbl 
FROM emp  
UNION ALL 
SELECT empno, ename, job, mgr, sal, comm, 'EMP2' tbl 
FROM emp2  
) 
SELECT empno, MAX(tbl) tbl, 
       CASE WHEN COUNT(DISTINCT ename) OVER(PARTITION BY empno)=COUNT(ename) OVER(PARTITION BY empno) 
            THEN ename  
       END ename, 
       CASE WHEN COUNT(DISTINCT job) OVER(PARTITION BY empno)=COUNT(job) OVER(PARTITION BY empno) 
            THEN job  
       END job, 
       CASE WHEN COUNT(DISTINCT mgr) OVER(PARTITION BY empno)=COUNT(mgr) OVER(PARTITION BY empno) 
            THEN mgr  
       END mgr, 
       CASE WHEN COUNT(DISTINCT sal) OVER(PARTITION BY empno)=COUNT(sal) OVER(PARTITION BY empno) 
            THEN sal  
       END sal, 
       CASE WHEN COUNT(DISTINCT comm) OVER(PARTITION BY empno)=COUNT(comm) OVER(PARTITION BY empno) 
            THEN comm  
       END comm 
FROM x 
GROUP BY empno, ename, job, mgr, sal, comm 
HAVING COUNT(*)=1 
ORDER BY 1, 2