declare
@cmdtext
varchar
(8000
);declare
@userindex
int;
set@cmdtext=''
;set
@userindex=0
;while
@userindex
<
30beginif(
@userindex
!=29
)select
@cmdtext
=@cmdtext+'
select convert(varchar(10), create_time, 120) as create_time,
datediff(d, create_time, last_login_time) loginday
from '+
'dbo.user'+
convert
(varchar
,@userindex) +
'union all'+
char(10
); --
換行else
select
@cmdtext
=@cmdtext+'
select convert(varchar(10), create_time, 120) as create_time,
datediff(d, create_time, last_login_time) loginday
from '+
'dbo.user'+
convert
(varchar
,@userindex
) ;set
@userindex
=@userindex+1
;end
;select
@cmdtext='
select u.create_time,sum(registernum) as registernum,
sum(firstday) as firstday, sum(twoday) as twoday,
sum(thirdday) as thirdday, sum(fourday) as fourday,
sum(fiveday) as fiveday,sum(sixday) as sixday,
sum(sevenday) as sevenday, sum(others) as others
from (
select create_time, count(create_time) as registernum,
case when loginday = 0 then count(create_time) else 0 end as firstday,
case when loginday = 1 then count(create_time) else 0 end as twoday,
case when loginday = 2 then count(create_time) else 0 end as thirdday,
case when loginday = 3 then count(create_time) else 0 end as fourday,
case when loginday = 4 then count(create_time) else 0 end as fiveday,
case when loginday = 5 then count(create_time) else 0 end as sixday,
case when loginday = 6 then count(create_time) else 0 end as sevenday,
case when loginday > 6 then count(create_time) else 0 end as others
from
(select t.create_time, t.loginday
from('
+@cmdtext+'
) t) tt
group by tt.create_time, tt.loginday
) ugroup by u.create_time
order by u.create_time';
--print @cmdtext
exec
(@cmdtext
);
本來如果到此為止，問題就完了，但是這個資料庫例項所在伺服器是美國時間，我們要按中國時間來統計，所以我就把上面其中的一段的指令碼做了如下改寫
@userindex
!=29
)select
@cmdtext
=@cmdtext+'
select convert(varchar(10), dateadd(hh, 15,create_time), 120) as create_time,
datediff(d, create_time, last_login_time) loginday
from '+
'dbo.user'+
convert
(varchar
,@userindex) +
'union all'+
char(10
); --
換行else
select
@cmdtext
=@cmdtext+'
select convert(varchar(10), dateadd(hh, 15,create_time), 120) as create_time,
datediff(d, create_time, last_login_time) loginday
from '+
'dbo.user'+
convert
(varchar
,@userindex
) ;set
@userindex
=@userindex+1
; 下面問題來了，如圖所示(執行時間時間是2007-7-26)，怎麼2010-7-26的資料在twoday列是198，2010-7-25註冊的使用者第三天還有148個登入，明顯錯了
乙個錯誤
select
datediff
(d,
'2010-7-25 0:30',
'2010-7-26 23:59')
--加上15個小時後
select
datediff
(d,
'2010-7-25 15:30',
'2010-7-27 15:59')
上面查詢結果是1 和 2 ，問題就出在這裡。所以把指令碼改寫後，就ok了。如果以後碰到類似問題，一定要注意！
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