SQL利用Function创建长整形的唯一ID示例代码

Create function dbo.pk()
returns bigint
as
begin 
 declare @pk as bigint,@fix bigint,@idx int,@ts as datetime
 set @ts = GETDATE()
 set @pk = convert(bigint,convert(varchar(6),@ts,12) + replace(convert(varchar(12),@ts,114),':',''))*10000
 select @idx = A*10000
 from vRand
 return (@pk + @idx)
end
go

declare @tab as table(pk bigint)
declare @i as integer
set @i =0
while(@i<10000)
begin
insert @tab
select dbo.pk() 
set @i = @i+1
end
select pk,count(1) cnt
from @tab
 group by pk
 having COUNT(1)>1

CREATE function dbo.pks(@count as int)
returns @pks table(pk bigint,id int)
as
begin 
  declare @pk as bigint,@fix bigint,@idx int,@ts as datetime,@lop int,@i int
  set @ts = GETDATE()
  set @pk = convert(bigint,'1'+convert(varchar(6),@ts,12) + replace(convert(varchar(11),@ts,114),':',''))*10000
  set @idx =0
  set @lop = CEILING(@count/10000.0) 
  set @i = 1
  while(@lop >0)
  begin
    set @pk = @pk + 10000
    set @idx = 0
    while(@idx<10000 and @idx<@count)
    begin
      insert @pks(pk,id)
      values(@pk+@idx,@idx+ @i)
      set @idx = @idx +1
    end
    set @lop = @lop -1
    set @i = @i+10000
  end
  return
end
go

select * from dbo.pks(500000)