oracle数据存在就修改，不存在就创建

merge into SYS_LOG A 
using (select '15' ID,'888' LOG_TYPE from dual) B on (A.ID = B.ID)
when matched then
	update set A.LOG_TYPE = B.LOG_TYPE
when not matched then
	insert (ID,LOG_TYPE)values(B.ID, B.LOG_TYPE);

merge语法

MERGE [INTO [schema .] table [t_alias]
USING [schema .] { table | view | subquery } [t_alias]
ON ( condition )
WHEN MATCHED THEN merge_update_clause   -- 存在
WHEN NOT MATCHED THEN merge_insert_clause;    -- 不存在