自已的sql server练习小记

print getdate();

print datediff(year,'1987-09-13',getdate())

select * from CallRecords

select top 5 *,'通话时间(秒)'=DATEDIFF(s,CallRecords.StartDateTime,CallRecords.EndDateTime)
from CallRecords order by '通话时间(秒)' desc

select 'jian',* from CallRecords

select SUM(t1.通话时间) from(

select 通话时间=DATEDIFF(s,CallRecords.StartDateTime,CallRecords.EndDateTime) from CallRecords where TelNum like '0%'
) as t1

print datepart(year,getdate())

select top 3 CallerNumber,

通话时间=sum(datediff(s,startDateTime,endDatetime))

from CallRecords

where DATEDIFF(mm,StartDateTime,'2010-07-12')=0

group by CallerNumber
order by 通话时间 desc

select top 3 CallerNumber,

通话次数=COUNT(CallRecords.Id)

from CallRecords

where DATEDIFF(mm,StartDateTime,'2010-07-12')=0

group by CallerNumber

order by 通话次数 desc