下面是一个小小的例子：
drop table if exists xh_yw.test;
create unlogged table xh_yw.test (
userid int8,
username varchar2(100),
CONSTRAINT test_primary_key PRIMARY KEY (userid)
);
select * from xh_yw.test;
-- 不存在则新增，存在则更新(类似mysql:on duplicate update操作) -- https://blog.csdn.net/weixin_34307464/article/details/91936020
insert into xh_yw.test(userid,username) values(1,'boonya') on conflict(userid) do update set username='boonya_update' ;
-- 批量修改数据语句
update xh_yw.test a set username= t.username from (select unnest(array[1]) as userid,unnest(array['boonya_batch']) as username) as t where t.userid = a.userid;
