[sql server] 如何得到连续序号

--SQL2000

--1

select number from master..spt_values where type='p' --0-255

--2
select top 10000 id=identity(int,1,1) into #t from sysobjects,syscolumns

--SQL2005生成系列号（行号）两种方式
--1.用CTE递归测试
;WITH t AS
(
SELECT 1 AS num
UNION ALL
SELECT num+1
FROM t
WHERE num<100000
)
SELECT * FROM t
OPTION(MAXRECURSION 0)

--2.用通过系统表生成行号测试
SELECT TOP 100000 num=ROW_NUMBER()OVER(ORDER BY GETDATE())
FROM syscolumns a,syscolumns b

--3.生成一个数字表，效率非常高
create function dbo.fn_nums(@n as bigint)
returns table
as
return
with
t1 as (select 1 as c union all select 1),
t2 as (select 1 as c from t1 as a,t1 as b),
t3 as (select 1 as c from t2 as a,t2 as b),
t4 as (select 1 as c from t3 as a,t3 as b),
t5 as (select 1 as c from t4 as a,t4 as b),
t6 as (select 1 as c from t5 as a,t5 as b),
t7 as (select row_number() over(order by c) as n from t6)
select n from t7 where n<@n;
go
--测试

select * from dbo.fn_nums(1000)