--创建测试表： 
CREATE TABLE MM (ID NUMBER, NAME VARCHAR2(20)); 
CREATE TABLE MN (ID NUMBER, NAME VARCHAR2(20)); 
--插入数据 
INSERT INTO MM VALUES (1, ‘A‘); 
INSERT INTO MN VALUES (1, ‘B‘);

--测试Merge
MERGE INTO MN A 
USING MM B 
ON(A.ID=B.ID) 
WHEN MATCHED THEN 
UPDATE SET A.NAME = B.NAME 
WHEN NOT MATCHED THEN 
INSERT(A.ID,A.NAME) VALUES(B.ID, B.NAME);

SQL> SELECT * FROM MN;
 
        ID NAME
---------- --------------------
         1 A