MERGE [hint] INTO [schema ] table [t_alias] USING [schema ]{ table | view | subquery } [t_alias] ON ( condition ) WHEN MATCHED THEN merge_update_clause WHEN NOT MATCHED THEN merge_insert_clause;代码及说明

1.MERGE INTO test T1 2.USING (SELECT OWNER , OBJECT_NAME , MAX(ID) ID FROM T GROUP BY OWNER, OBJECT_NAME) T 3.ON (T.OWNER = T1.OWNER AND T.OBJECT_NAME = T1.TABLE_NAME) 4.WHEN MATCHED THEN UPDATE SET T1.ID = T.ID 5.WHEN NOT MATCHED THEN INSERT VALUES (T.ID, T.OWNER, T.OBJECT_NAME); 第一行 命名目标表并给别名T1 第二行 using子句提供merge操作的数据源，命名T 第三行 on子句指定合并的条件 第四行 when matched then 子句判定条件符合则对表T1做什么改变（或删除） 第五行 when not matched then 子句判断条件不符合则插入的操作

MERGE INTO 实现插入更新，作用与Kettle 插入更新效果相同。 MERGE INTO test_B T1 USING (SELECT * FROM test_A) T2 ON (T1.T_NAME = T2.T_NAME) WHEN MATCHED THEN UPDATE SET T1.T_COMMENT = T2.T_COMMENT, T1.T_KEY_COL = T2.T_KEY_COL WHEN NOT MATCHED THEN INSERT (T_NAME, T_COMMENT, T_KEY_COL) VALUES (T2.T_NAME, T2.T_COMMENT, T2.T_KEY_COL);