需求：根据project_id分组，project_lease_item_id排序对seq_number从1递增更新整个表中的数据
一、下图为更新之前的数据：
二、更新数据库的代码
数据库用的是oracle:
方案一：
update prj_project_lease_item p1
set p1.seq_number =
(select V.seq_number
FROM (select row_number() over(partition by p.project_id order by project_lease_item_id asc) seq_number,
p.project_lease_item_id
from prj_project_lease_item p) V
where V.project_lease_item_id = p1.project_lease_item_id)
where exists
(select p.project_id,
p.project_lease_item_id,
row_number() over(partition by p.project_id order by project_lease_item_id asc) seq_number
from prj_project_lease_item p
where p.project_lease_item_id = p1.project_lease_item_id);方案二：
declare
v_temp prj_project_lease_item%rowtype;
begin
for v_temp in (select p.project_id,
p.project_lease_item_id,
row_number() over(partition by p.project_id order by project_lease_item_id asc) seq_number
from prj_project_lease_item p) loop
update prj_project_lease_item p2
set p2.seq_number = v_temp.seq_number
where p2.project_lease_item_id = v_temp.project_lease_item_id;
end loop;
end;