更新语句在我的查询中不起作用

Question

with t as (
       select 'AA-00001152' itemid from dual union all
       select 'AA-00001152' from dual union all
       select 'AA-00001153' from dual union all
       select 'AA-00001154' from dual union all
       select 'AA-00001154' from dual union all
       select 'CC-254565' from dual union all
       select 'AA-00001156' from dual union all
       select 'AA-00001156' from dual union all
       select 'BB-00001200' from dual
      )
select 14999 + dense_rank() over(order by itemid) as seq_no,
       itemid 
from  t
order by seq_no

这里我为多个itemId生成了seq_no，但我试图在seq_no列中更新，这会抛出错误，说子查询返回多行。请帮助更新查询。感谢。

我的更新查询： -

update test
    set seq_num =14999 + dense_rank() over(order by itemid) 
    where item_type='non_product')

Answer 1

在SQL Server中，您可以使用可更新的CTE：

with toupdate as (
      select dense_rank() over (order by itemid) as seqnum,
             t.* 
      from  t
     )
update toupdate
    set seq_num = 14999 + seqnum
    where item_type = 'non_product';

但是，我怀疑你并没有真正使用SQL Server。此语法在大多数其他数据库中不起作用。