sql-server-2005 - 如何在已经有记录的表上创建行计数？

Question

我有一个表格，表格中已经填充了 5000 行。

我有一个名为 SEQN 的列。

我想用行数填充此列。

我在用：

Microsoft SQL Server Management Studio 9.00.4035.00 Microsoft Analysis Services 客户端工具 2005.090.4035.00 Microsoft 数据访问组件 (MDAC) 6.1.7601.17514 Microsoft MSXML 3.0 4.0 5.0 6.0 Microsoft Internet Explorer 9.0.8112.16421 Microsoft .NET Framework 2.0.50727.56017 操作系统 6.1.7

预先感谢您的协助。

SQL新手

Answer 1

declare @Foo as Table ( FooId Int Identity, Sequence Int, Timestamp DateTime );
insert into @Foo ( Sequence, Timestamp ) values
  ( 42, '20010203 10:18:05' ), ( 18, '20100508 22:18:05' ), ( NULL, '19960316 19:00:00' );

select * from @Foo order by Sequence;

update Foo
  set Sequence = S
  from ( select Sequence, Row_Number() over ( order by Timestamp ) as S from @Foo ) as Foo;

select * from @Foo order by Sequence;

update Foo
  set Sequence = S
  from ( select Sequence, Row_Number() over ( order by Timestamp desc ) as S from @Foo ) as Foo;

select * from @Foo order by Sequence;