MERGE INTO USER_TEST T1
USING (SELECT ‘1001‘ AS ID,‘王睿‘ AS NAME FROM dual) T2
ON ( T1.ID=T2.ID)
WHEN MATCHED THEN
UPDATE SET T1.NAME = T2.NAME
WHEN NOT MATCHED THEN
INSERT (NAME) VALUES(T2.NAME);
commit;
原文：http://www.cnblogs.com/nihaorz/p/5332716.html