Mybatis常用语句

常用语句，更新插入通用

<update id="saveOrUpdate" parameterType="com.baidu.City">

<![CDATA[
MERGE INTO CITY a   
       USING (
       select count(1) co from CITY where id = #{id}
       ) b   
       ON (b.co<>0)  
       WHEN MATCHED THEN   
       UPDATE  SET a.city = #{city}   where a.id= #{id}
       WHEN NOT MATCHED THEN   
       INSERT  (id,city)  VALUES (#{id},#{city})  
]]>
</update>