您可以帮我过滤过去xxxx天未联系的客户吗？ e.i 45
SELECT TOP 1000 [ID]
,[dates]
,[companies]
FROM [company].[dbo].[Contact]
注意：有些公司在xxxx日被联系了多次。
我认为获取最新日期将获得准确的结果。
ID dates companies
2017/01/02 Facebook
2017/01/03 Chevron
2017/01/05 AFLAC
2017/01/09 Applied Industrial Technologies
2017/01/11 Charter Communications
2017/01/12 Coca-Cola
2017/01/13 Dow Chemical
2017/01/17 Foot Locker
2017/01/18 General Dynamics
2017/01/20 Humana
2017/01/25 Imation
2017/01/26 Kimberly-Clark
2017/01/27 3M
2017/01/30 Facebook
2017/01/31 Chevron
2017/02/01 Foot Locker
2017/02/03 General Dynamics
2017/02/06 Humana
2017/02/10 Imation
2017/02/17 Kimberly-Clark
2017/02/20 3M
2017/02/21 Public Storage
2017/02/22 Qualcomm
2017/02/24 Sealy
2017/02/28 Steelcase
2017/02/02 Textron
2017/02/06 Men's Wearhouse
2017/02/08 Toll Brothers
2017/02/09 Tractor Supply
2017/02/13 USG
2017/02/14 Valspar
2017/02/15 Waste Management
2017/02/20 Williams-Sonoma
2017/02/21 Yahoo
2017/02/23 Union Pacific
2017/02/24 Foot Locker
2017/02/27 General Dynamics
2017/02/28 Humana
2017/03/01 Imation
2017/03/02 Kimberly-Clark
2017/03/03 3M
2017/03/06 Public Storage
2017/03/09 Qualcomm
2017/03/10 Sealy
2017/03/13 Steelcase
2017/03/14 Textron
2017/03/17 Men's Wearhouse
2017/03/23 Toll Brothers
2017/03/24 Tractor Supply
2017/03/27 USG
2017/03/01 Valspar
2017/03/03 Waste Management
2017/03/06 Williams-Sonoma
2017/03/07 Yahoo
2017/03/08 Union Pacific
2017/03/09 Foot Locker
2017/03/13 General Dynamics
2017/03/15 Humana
2017/03/22 Imation
2017/03/24 Kimberly-Clark
2017/03/27 3M
2017/03/28 Capital One Financial
2017/03/29 CBS
2017/04/03 Citigroup
2017/04/05 E*Trade Financial
2017/04/06 El Paso
2017/04/07 Goodrich
2017/04/10 Hanesbrands
2017/04/11 International Paper
2017/04/12 Eastman Kodak
2017/04/20 Kraft Foods
2017/04/25 LSI
2017/04/26 Macy's
2017/04/27 Brunswick
2017/04/28 Meredith
2017/04/03 Manpower
2017/04/04 NCR
2017/04/05 Oracle
2017/04/07 Pepsi Bottling
2017/04/10 Pfizer
2017/04/13 Penn National Gaming
2017/04/14 Prudential Financial
2017/04/17 RadioShack
2017/04/18 Regal Entertainment Group
2017/04/24 SanDisk
2017/04/26 Facebook
2017/05/01 Chevron
2017/05/04 AFLAC
2017/05/05 Applied Industrial Technologies
2017/05/08 Charter Communications
2017/05/09 Coca-Cola
2017/05/10 Dow Chemical
2017/05/11 Foot Locker
2017/05/15 General Dynamics
2017/05/16 Humana
2017/05/17 Imation
2017/05/19 Kimberly-Clark
2017/05/24 3M
2017/05/25 Facebook
2017/05/26 Chevron
2017/05/01 Foot Locker
2017/05/04 General Dynamics
2017/05/08 Humana
2017/05/12 Imation
2017/05/15 Kimberly-Clark
2017/05/16 3M
2017/05/18 Public Storage
2017/05/19 Qualcomm
2017/05/22 Sealy
2017/05/24 Steelcase
2017/05/26 Textron
2017/05/29 Men's Wearhouse
2017/05/30 Toll Brothers
2017/05/31 Tractor Supply
2017/06/07 USG
2017/06/09 Facebook
2017/06/13 Chevron
2017/06/14 AFLAC
2017/06/15 Applied Industrial Technologies
2017/06/19 Charter Communications
2017/06/20 Coca-Cola
2017/06/22 Dow Chemical
2017/06/23 Foot Locker
2017/06/26 General Dynamics
2017/06/28 Humana
2017/06/01 Imation
2017/06/02 Kimberly-Clark
2017/06/05 3M
2017/06/06 Facebook
2017/06/07 Chevron
2017/06/08 Foot Locker
2017/06/12 General Dynamics
2017/06/13 Humana
2017/06/14 Imation
2017/06/16 Kimberly-Clark
2017/06/20 3M
2017/06/21 Public Storage
2017/06/22 Qualcomm
2017/06/29 Sealy
2017/06/30 Steelcase
2017/07/11 Textron
2017/07/12 Men's Wearhouse
2017/07/13 Toll Brothers
2017/07/14 Tractor Supply
2017/07/19 USG
2017/07/21 Facebook
2017/07/24 Chevron
2017/07/25 AFLAC
2017/07/26 Applied Industrial Technologies
2017/07/27 Charter Communications
2017/08/01 Coca-Cola
2017/08/02 Dow Chemical
2017/08/10 Foot Locker
2017/08/11 General Dynamics
2017/08/15 Humana
2017/08/16 Imation
2017/08/17 Kimberly-Clark
2017/08/21 3M
2017/08/23 Facebook
2017/08/24 Chevron
2017/08/25 Foot Locker
2017/08/29 General Dynamics
2017/08/30 Humana
2017/08/31 Imation
2017/09/07 Kimberly-Clark
2017/09/08 3M
2017/09/13 Public Storage
2017/09/14 Qualcomm
2017/09/15 Sealy
2017/09/20 Steelcase
2017/09/21 Textron
2017/09/22 Men's Wearhouse
2017/09/25 Toll Brothers
2017/09/26 Tractor Supply
2017/09/27 USG
2017/09/04 Facebook
2017/09/05 Chevron
2017/09/06 AFLAC
2017/09/11 Applied Industrial Technologies
2017/09/13 Charter Communications
2017/09/14 Coca-Cola
2017/09/15 Dow Chemical
2017/09/20 Foot Locker
2017/09/21 General Dynamics
2017/09/22 Humana
2017/09/26 Imation
2017/09/27 Kimberly-Clark
2017/09/29 3M
2017/10/02 Facebook
2017/10/03 Chevron
2017/10/05 Foot Locker
2017/10/11 General Dynamics
2017/10/12 Humana
2017/10/16 Imation
2017/10/18 Kimberly-Clark
2017/10/19 3M
2017/10/20 Public Storage
2017/10/23 Qualcomm
2017/10/24 Sealy
2017/10/26 Steelcase
答案 0 :(得分：2)
使用not exists()：
select distinct companies
from [company].[dbo].[Contact] c
where not exists (
select 1
from [company].[dbo].[Contact] i
where i.companies = c.companies
and i.dates >= convert(date,dateadd(day,-45,getdate()))
)
如果您有一张companies表格，那么您可以在distinct表格中使用该表格代替contact。这样，您还可以返回companies中没有条目的contact。
select *
from [company].[dbo].[companies] c
where not exists (
select 1
from [company].[dbo].[Contact] i
where i.companies = c.companies
and i.dates >= convert(date,dateadd(day,-45,getdate()))
)
使用having()子句聚合的另一个选项仅返回companies小于45天前的max(dates);还返回最新的联系日期：
select
companies
, LastContact = max(dates)
from [company].[dbo].[Contact] c
group by companies
having max(dates)<convert(date,dateadd(day,-45,getdate()))
rextester演示：http://rextester.com/OJER22556
返回：
+---------------------------+-------------+
| companies | LastContact |
+---------------------------+-------------+
| Brunswick | 2017-04-27 |
| Capital One Financial | 2017-03-28 |
| CBS | 2017-03-29 |
| Citigroup | 2017-04-03 |
| E*Trade Financial | 2017-04-05 |
| Eastman Kodak | 2017-04-12 |
| El Paso | 2017-04-06 |
| Goodrich | 2017-04-07 |
| Hanesbrands | 2017-04-10 |
| International Paper | 2017-04-11 |
| Kraft Foods | 2017-04-20 |
| LSI | 2017-04-25 |
| Macy's | 2017-04-26 |
| Manpower | 2017-04-03 |
| Meredith | 2017-04-28 |
| NCR | 2017-04-04 |
| Oracle | 2017-04-05 |
| Penn National Gaming | 2017-04-13 |
| Pepsi Bottling | 2017-04-07 |
| Pfizer | 2017-04-10 |
| Prudential Financial | 2017-04-14 |
| RadioShack | 2017-04-17 |
| Regal Entertainment Group | 2017-04-18 |
| SanDisk | 2017-04-24 |
| Union Pacific | 2017-03-08 |
| Valspar | 2017-03-01 |
| Waste Management | 2017-03-03 |
| Williams-Sonoma | 2017-03-06 |
| Yahoo | 2017-03-07 |
+---------------------------+-------------+
答案 1 :(得分：0)
declare @date datetime = getdate()
select * from [company].[dbo].[contact] where DATEDIFF(DAY, dates, @date) >= 45
由于对过滤谓词执行操作不利于性能（防止使用索引等），因此更有效的方法是：
declare @date datetime = getdate()
select
id
,dates
,company
from (
select
*,
DATEDIFF(DAY, dates, @date) as daysSinceContact
from
[company].[dbo].[contact]
) as c
where
daysSince >= 45
或使用CTE
declare @date datetime = getdate()
;with c as (
select
*,
DATEDIFF(DAY, dates, @date) as daysSinceContact
from
[company].[dbo].[contact]
)
select
id
,dates
,company
from
c
where
daysSince >= 45
答案 2 :(得分：0)
SELECT Companies
,[Dates]
,DATEDIFF(Day, [Dates], CAST(Getdate() AS DATE)) AS [DaysHaven't Been Contacted Past45 days]
FROM #Temp o
WHERE DATEDIFF(Day, [Dates], CAST(Getdate() AS DATE)) >= 45
ORDER BY [Dates] DESC