How to get difference in value over 15min interval?

Question

I have this table:

The 2 important columns here are domainid and Soldtickets.

Soldtickets show how many tickets were sold today.

I make a call to my server and it tells me that I made the call at "2016-03-30 14:18:01.4130000" and that 0 tickets have been sold for the Domain with DomainId 53.

I am trying to figure out how I can find the difference.

I call the server every two minutes and I get data. I want to check the data that I have got the last 15 minutes and see if soldtickets has changes and how much.

Example:

At :

2016-03-30 14:18:01.4130000

For DomainId

53

0 Tickets Sold

At :

2016-03-30 14:26:01.4130000

For DomainId

53

5 Tickets Sold(5 tickest total for today)

At :

2016-03-30 14:30:01.4130000

For DomainId

53

5 Tickets Sold ( same as before, NO change)

I want to know how many were sold the last 15 minutes. In this case it would be 5 tickets but what if at

2016-03-30 14:44:01.4130000 I get back that I have sold a total of 7 tickets for today, then the difference for the last 15 minutes is 2 tickets.

So far I can get the inserts of the last 15 minutes like so:

DECLARE @LatestFifteenMinTickets TABLE
(
    DomainId bigint, 
    SoldTickets bigint
)

DECLARE @FifteenMinDate datetime2


SELECT @FifteenMinDate = DATEADD(minute, -15, GETDATE())

INSERT INTO @LatestFifteenMinTickets(DomainId,SoldTickets)
            SELECT DomainId, SoldTickets  
            FROM DomainDetailDataHistory
            WHERE [Date] > @FifteenMinDate

I have tried a few scenarios but I honestly don't know how to conntinue.

How can I do this?

EDIT:

Lets say If i get back that I have sold 0 tickets today at 13:00. And the next 15 minutes I get 15 inserts where soldtickets is also 0. the diffirence here is nothing since 0-0 = 0 Which means I have sold 0 tickets the last 15 minutes AND sold 0 tickets for the entire day (so far). But at 14:00 I get back info from server that 10 tickets are sold. The next 15 minutesI keep getting sold tickets = 10 which means that the last 15 min i have sold 0 tickets but for the entire day i have sold 10 tickets –

I Need to check the soldtickets columnt for every unique DomainId and see if there is any difference to the most current one. If there Is i want to know what the difference is in numbers

Answer 1

只要你组@LatestFifteenMinTickets由表域ID，并采取之间的差异MIN(SoldTickets)和MAX(SoldTickets)。这将为您提供表变量中收集的时间段内每个域的售出票数：

SELECT
  DomainId,
  SoldToday         = MAX(SoldTickets),
  SoldSince15MinAgo = MAX(SoldTickets) - MIN(SoldTickets)
FROM
  @LatestFifteenMinTickets
GROUP BY
  DomainId
;

除非SoldTickets可以减少也可以增加（可以退票吗？），在这种情况下，您应该取第一个和最后一个值，而不是最小值和最大值。但是为了能够做到这一点，您的表变量中也应该有Date属性。然后可以使用分析函数FIRST_VALUE和LAST_VALUE组织计算：

SELECT DISTINCT
  DomainId,
  SoldToday         = LAST_VALUE(SoldTickets) OVER (PARTITION BY DomainId ORDER BY [Date] ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING),
  SoldSince15MinAgo = LAST_VALUE(SoldTickets) OVER (PARTITION BY DomainId ORDER BY [Date] ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
                   - FIRST_VALUE(SoldTickets) OVER (PARTITION BY DomainId ORDER BY [Date] ASC ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)
FROM
  @LatestFifteenMinTickets
;