Question

我有一个select语句，我需要将其转换为Update语句。

SELECT GUID,seq original_seq_no, ROW_NUMBER()
OVER ( PARTITION BY GUID ORDER BY seq) AS new_seq_no
FROM CHK_SEQ;

上面的查询实际上是什么，假设我有一个具有唯一GUID的多个记录，并且表CHK_SEQ中列SEQ的值是6,9,10。然后运行上面的查询将SEQ的值更改为1,2,3，即new_seq_no。

任何人都可以帮助我。

感谢。

Answer 1

试试这个（Sql-Server 2005及以上版本）：

With cte as (
  Select GUID,seq, row_number() over ( partition by GUID order by seq) AS new_seq_no
  From CHK_SEQ
)
Update c
Set c.seq = new_seq_no
From CHK_SEQ c 
     Join cte on c.Guid = cte.Guid and c.seq = cte.seq;

Answer 2

试试这个，

with cte 
AS
(
SELECT GUID,seq original_seq_no, ROW_NUMBER()
OVER ( PARTITION BY GUID ORDER BY seq) AS new_seq_no
FROM CHK_SEQ
)

update  CHK_SEQ
set     CHK_SEQ.seq = r.new_seq_no
from    cte r
where CHK_SEQ.seq = r.original_seq_no AND CHK_SEQ.GUID= r.GUID;

Answer 3

merge into CHK_SEQ 
using
    SELECT rowid as rid, 
           ROW_NUMBER() OVER (PARTITION BY GUID ORDER BY seq) AS new_seq_no
    FROM CHK_SEQ
) t on (chk_seq.rowid = t.rid)
when matched then update
   set seq = new_seq_no;

如何将select转换为update语句

3 个答案: