表中NULL的处理？
表结构如下：
datetime A B C D E F
07/04/03 11:10:00 12 13 null 15 17 20
07/04/03 11:11:00 14 null 18 null 11 null
07/04/03 11:12:00 17 15 17 null 15 23
07/04/03 11:13:00 29 30 31 36 24 17
现在要求当表中某字段为空时，就用紧挨它的一个不为空的数据填补它。
请问各位高手怎么实现啊？(datetime 为主键)
[解决办法]
不明白,帮你定 紧挨它是那个数啊.结果不明确呢
[解决办法]
VB为例：
att = 07/04/03 11:11:00
set rs = server.createObject( "adodb.recordset ")
rs.open "select * from [表] where datetime= "&att,conn,1,3
if trim(rs( "B ")) <> " " then
else
rs( "B ") = trim(rs( "C "))
end if
rs.update
rs.close
set rs = nothing
试试看！
[解决办法]
create table tass(da datetime, A int, B int, C int, D int, E int, F int)
insert tass select '07/04/03 11:10:00 ' ,12 ,13, null, 15, 17, 20
union all select '07/04/03 11:11:00 ', 14, null, 18, null, 11, null
union all select '07/04/03 11:12:00 ', 17 ,15 ,17, null, 15, 23
union all select '07/04/03 11:13:00 ', 29, 30, 31, 36, 24, 17
declare @a varchar(10),@b varchar(10)
declare @v varchar(100)
declare cur cursor for
select name from syscolumns where id=object_id( 'tass ') order by colid
open cur
fetch next from cur into @a
while @@fetch_status=0
begin
fetch next from cur into @b
select @@fetch_status,@a, @b
if @@fetch_status=0 and @a <> 'da '
begin
set @v= 'update tass set '+@b+ '= '+@a+ '+1 from tass where '+@b+ ' is null '
exec(@v)
select @v
end
set @a=@b
end
close cur
deallocate cur
select * from tass
[解决办法]
用两个游标进行循环进行更新!根据日期排序!
[解决办法]
create table tass(da datetime, A int, B int, C int, D int, E int, F int)
insert tass select '07/04/03 11:10:00 ' ,12 ,13, null, 15, 17, 20
union all select '07/04/03 11:11:00 ', 14, null, 18, null, 11, null
union all select '07/04/03 11:12:00 ', 17 ,15 ,17, null, 15, 23
union all select '07/04/03 11:13:00 ', 29, 30, 31, 36, 24, 17
--select * from tass
select da,
isnull(A,(select top 1 A from tass where da> a.da and A is not null order by da)) as A,
isnull(B,(select top 1 B from tass where da> a.da and B is not null order by da)) as B,
isnull(C,(select top 1 C from tass where da> a.da and C is not null order by da)) as C,
isnull(D,(select top 1 D from tass where da> a.da and D is not null order by da)) as D,
isnull(E,(select top 1 E from tass where da> a.da and E is not null order by da)) as E,
isnull(F,(select top 1 F from tass where da> a.da and F is not null order by da)) as F
from tass a
order by da
drop table tass
