springboot mybatis merge into 用法

例子：

<update id="insert" parameterType="***.***.***.实体">
   merge into 表名 a
     using (select 1 from dual)
       on (a.字段1 = #{参数} and a.字段2 = #{参数2})
       when not matched then
         insert (字段1,字段2,字段3)
     	   values(#{参数1,jdbcType=VARCHAR},#{参数2,jdbcType=VARCHAR},#{参数3,jdbcType=VARCHAR})
       when matched then
         update set counts = counts + 1, last_time = sysdate, 字段1 = #{参数1,jdbcType=VARCHAR}
</update>