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Imagine a employee who works in a company whos having a contract to work on a specific task, he comes in and goes on start and end date respectively. I want to get the interval at which the employee comes to office without any absence.
Example Data:
DECLARE #TimeClock TABLE (PunchID INT IDENTITY, EmployeeID INT, PunchinDate DATE)
INSERT INTO #TimeClock (EmployeeID, PunchInDate) VALUES
(1, '2020-01-01'), (1, '2020-01-02'), (1, '2020-01-03'), (1, '2020-01-04'),
(1, '2020-01-05'), (1, '2020-01-06'), (1, '2020-01-07'), (1, '2020-01-08'),
(1, '2020-01-09'), (1, '2020-01-10'), (1, '2020-01-11'), (1, '2020-01-12'),
(1, '2020-01-13'), (1, '2020-01-14'), (1, '2020-01-16'),
(1, '2020-01-17'), (1, '2020-01-18'), (1, '2020-01-19'), (1, '2020-01-20'),
(1, '2020-01-21'), (1, '2020-01-22'), (1, '2020-01-23'), (1, '2020-01-24'),
(1, '2020-01-25'), (1, '2020-01-26'), (1, '2020-01-27'), (1, '2020-01-28'),
(1, '2020-01-29'), (1, '2020-01-30'), (1, '2020-01-31'),
(1, '2020-02-01'), (1, '2020-02-02'), (1, '2020-02-03'), (1, '2020-02-04'),
(1, '2020-02-05'), (1, '2020-02-06'), (1, '2020-02-07'), (1, '2020-02-08'),
(1, '2020-02-09'), (1, '2020-02-10'), (1, '2020-02-12'),
(1, '2020-02-13'), (1, '2020-02-14'), (1, '2020-02-15'), (1, '2020-02-16');
--the output shall look like this '2020-01-01 to 2020-02-10' as this is the interval at which the employee comes without any leave
SELECT 1 AS ID, FORMAT( getdate(), '2020-01-01') as START_DATE, FORMAT( getdate(), '2020-01-10') as END_DATE union all
SELECT 1 AS ID, FORMAT( getdate(), '2020-01-11') as START_DATE, FORMAT( getdate(), '2020-01-15') as END_DATE union all
SELECT 1 AS ID, FORMAT( getdate(), '2020-01-21') as START_DATE, FORMAT( getdate(), '2020-01-31') as END_DATE union all
SELECT 1 AS ID, FORMAT( getdate(), '2020-02-01') as START_DATE, FORMAT( getdate(), '2020-02-10') as END_DATE
--the output shall look like this '2020-01-01 to 2020-01-15' and '2020 01-21 to 2020-02-10'as these are the intervals at which the employee comes without any leave
Using the example data provided we can query the table like this:
;WITH iterate AS (
SELECT *, DATEADD(DAY,1,PunchinDate) AS NextDate
FROM #TimeClock
), base AS (
SELECT *
FROM (
SELECT *, CASE WHEN DATEADD(DAY,-1,PunchInDate) = LAG(PunchinDate,1) OVER (PARTITION BY EmployeeID ORDER BY PunchinDate) THEN PunchInDate END AS s
FROM iterate
) a
WHERE s IS NULL
), rCTE AS (
SELECT EmployeeID, PunchInDate AS StartDate, PunchInDate AS EndDate, NextDate
FROM base
UNION ALL
SELECT a.EmployeeID, a.StartDate, r.PunchInDate, r.NextDate
FROM rCTE a
INNER JOIN iterate r
ON a.NextDate = r.PunchinDate
AND a.EmployeeID = r.EmployeeID
)
SELECT EmployeeID, StartDate, MAX(EndDate) AS EndDate, DATEDIFF(DAY,StartDate,MAX(EndDate)) AS Streak
FROM rCTE
GROUP BY rCTE.EmployeeID, rCTE.StartDate
This is known as a recursive common table expression, and allows us to compare values between related rows. In this case we're looking for rows where they follow a streak, and we want o re-start that streak anytime we encounter a break. We're using a windowed function called LAG to look back a row to the previous value, and compare it to the one we have now. If it's not yesterday, then we start a new streak.
EmployeeID StartDate EndDate Streak
------------------------------------------
1 2020-01-01 2020-01-15 14
1 2020-01-17 2020-02-10 24
1 2020-02-12 2020-02-16 4
Not sure if this or similar question is asked already but i could not find one.
The Requirement to create range of IDs while the Value is not changed. This schema can be used:
declare #mytable as table(ID int, Val int)
insert into #mytable values
(1, 1),
(2, 1),
(3, 1),
(4, 2),
(5, 2),
(6, 2),
(7, 2),
(8, 1),
(9, 1),
(10, 1),
(11, 4),
(12, 4),
(13, 4),
(14, 4),
(15, 4),
(16, 5);
And the expected result would be
StartID EndID Val
1 3 1
4 7 2
8 10 1
11 15 4
16 16 5
Now I can achieve this by running cursor and If n case the number of records will be millions, I think, cursor will be slower. I hope it can be written using some compound query but could not figure-out how.
So I need help in writing that kind of query and needless to mention yet, it is not a school/collage project/assignment.
This is a gaps-and-islands scenario where you're trying to group records together based on the change in Val.
This is using window functions to determine when the Val changes, and assign the island_nbr.
Answer:
select min(b.ID) as StartID
, max(b.ID) as EndID
, max(b.Val) as Val
from (
select a.ID
, a.Val
, sum(a.is_chng_flg) over (order by a.ID asc) as island_nbr
from (
select m.ID
, m.Val
, case lag(m.Val, 1, m.Val) over (order by m.ID asc) when m.Val then 0 else 1 end is_chng_flg
from #mytable as m
) as a
) as b
group by b.island_nbr --forces the right records to show up
order by 1
This is a gaps-and-islands problem. But the simplest method is the difference of row numbers:
select min(id) as startId, max(id) as endId, val
from (select t.*,
row_number() over (order by id) as seqnum,
row_number() over (partition by val order by id) as seqnum_v
from #mytable t
) t
group by (seqnum - seqnum_v), val
order by startId;
Strange problem with a GROUP BY and HAVING clause on SQL Server 2014.
It's distinctly possible I've done something wrong, but I cannot make sense of this.
Here's the setup data:
create table #accounts(accountid int)
create table #data(accountid int, categoryid int, asofdate date, datavalue numeric(20, 10))
insert into #accounts
values
(1),(2),(3)
insert into #data
values
(1, 10, '1/31/2015', 0),
(1, 10, '2/28/2015', 10),
(1, 10, '3/31/2015', 20),
(2, 10, '1/31/2015', 0),
(2, 10, '2/28/2015', 15),
(2, 10, '3/31/2015', 25),
(3, 10, '1/31/2015', 0),
(3, 10, '2/28/2015', 7),
(3, 10, '3/31/2015', 12)
This returns a single row... for 1/31/2015. The only date with a total of zero
select categoryid, asofdate, sum(datavalue) as totalvalue
from #accounts a
inner join #data d
on d.accountid = a.accountid
group by d.categoryid, d.asofdate
having sum(datavalue) = 0
Result is 10, '1/31/2015', 0
Yet, somehow the following does not return any rows... I'm basically asking it to give me the Max date from the first query. Why does this balk?
select categoryid, max(asofdate) as MaxAsOfDate, sum(datavalue) as totalvalue
from #accounts a
inner join #data d
on d.accountid = a.accountid
group by d.categoryid
having sum(datavalue) = 0
drop table #accounts
drop table #data
Yet it returns no rows... baffled.
SQL Fiddle here:
http://sqlfiddle.com/#!6/5e44cb/1
Simply, because you are Grouping by d.categoryid - And there is no grouping by this column, which would return 0 for sum(datavalue):
http://sqlfiddle.com/#!6/5e44cb/4 (it's 89)
If you could add your expected output to your post, we might be able to help you with the query you need.
By removing the GROUP BY asOfDate, you've removed any groups that have SUM()=0.
You should make your first query a derived table or CTE, and then do the MAX outside of it to get your desired results.
I have a table like below, What I need that for any particular fund and up to any particular date logic will sum the amount value. Let say I need the sum for 3 dates as 01/28/2015,03/30/2015 and 04/01/2015. Then logic will check for up to first date how many records are there in table . If it found more than one record then it'll sum the amount value. Then for next date it'll sum up to the next date but from the previous date it had summed up.
Id Fund Date Amount
1 A 01/20/2015 250
2 A 02/28/2015 300
3 A 03/20/2015 400
4 A 03/30/2015 200
5 B 04/01/2015 500
6 B 04/01/2015 600
I want result to be like below
Id Fund Date SumOfAmount
1 A 02/28/2015 550
2 A 03/30/2015 600
3 B 04/01/2015 1100
Based on your question, it seems that you want to select a set of dates, and then for each fund and selected date, get the sum of the fund amounts from the selected date to the previous selected date. Here is the result set I think you should be expecting:
Fund Date SumOfAmount
A 2015-02-28 550.00
A 2015-03-30 600.00
B 2015-04-01 1100.00
Here is the code to produce this output:
DECLARE #Dates TABLE
(
SelectedDate DATE PRIMARY KEY
)
INSERT INTO #Dates
VALUES
('02/28/2015')
,('03/30/2015')
,('04/01/2015')
DECLARE #FundAmounts TABLE
(
Id INT PRIMARY KEY
,Fund VARCHAR(5)
,Date DATE
,Amount MONEY
);
INSERT INTO #FundAmounts
VALUES
(1, 'A', '01/20/2015', 250)
,(2, 'A', '02/28/2015', 300)
,(3, 'A', '03/20/2015', 400)
,(4, 'A', '03/30/2015', 200)
,(5, 'B', '04/01/2015', 500)
,(6, 'B', '04/01/2015', 600);
SELECT
F.Fund
,D.SelectedDate AS Date
,SUM(F.Amount) AS SumOfAmount
FROM
(
SELECT
SelectedDate
,LAG(SelectedDate,1,'1/1/1900') OVER (ORDER BY SelectedDate ASC) AS PreviousDate
FROM #Dates
) D
JOIN
#FundAmounts F
ON
F.Date BETWEEN DATEADD(DAY,1,D.PreviousDate) AND D.SelectedDate
GROUP BY
D.SelectedDate
,F.Fund
EDIT: Here is alternative to the LAG function for this example:
FROM
(
SELECT
SelectedDate
,ISNULL((SELECT TOP 1 SelectedDate FROM #Dates WHERE SelectedDate < Dates.SelectedDate ORDER BY SelectedDate DESC),'1/1/1900') AS PreviousDate
FROM #Dates Dates
) D
If i change your incorrect sample data to ...
CREATE TABLE TableName
([Id] int, [Fund] varchar(1), [Date] datetime, [Amount] int)
;
INSERT INTO TableName
([Id], [Fund], [Date], [Amount])
VALUES
(1, 'A', '2015-01-28 00:00:00', 250),
(2, 'A', '2015-01-28 00:00:00', 300),
(3, 'A', '2015-03-30 00:00:00', 400),
(4, 'A', '2015-03-30 00:00:00', 200),
(5, 'B', '2015-04-01 00:00:00', 500),
(6, 'B', '2015-04-01 00:00:00', 600)
;
this query using GROUP BY works:
SELECT MIN(Id) AS Id,
MIN(Fund) AS Fund,
[Date],
SUM(Amount) AS SumOfAmount
FROM dbo.TableName t
WHERE [Date] IN ('01/28/2015','03/30/2015','04/01/2015')
GROUP BY [Date]
Demo
Initially i have used Row_number and month function to pick max date of every month and in 2nd cte i did sum of amounts and joined them..may be this result set matches your out put
declare #t table (Id int,Fund Varchar(1),Dated date,amount int)
insert into #t (id,Fund,dated,amount) values (1,'A','01/20/2015',250),
(2,'A','01/28/2015',300),
(3,'A','03/20/2015',400),
(4,'A','03/30/2015',200),
(5,'B','04/01/2015',600),
(6,'B','04/01/2015',500)
;with cte as (
select ID,Fund,Amount,Dated,ROW_NUMBER() OVER
(PARTITION BY DATEDIFF(MONTH, '20000101', dated)ORDER BY dated desc)AS RN from #t
group by ID,Fund,DATED,Amount
),
CTE2 AS
(select SUM(amount)Amt from #t
GROUP BY MONTH(dated))
,CTE3 AS
(Select Amt,ROW_NUMBER()OVER (ORDER BY amt)R from cte2)
,CTE4 AS
(
Select DISTINCT C.ID As ID,
C.Fund As Fund,
C.Dated As Dated
,ROW_NUMBER()OVER (PARTITION BY RN ORDER BY (SELECT NULL))R
from cte C INNER JOIN CTE3 CC ON c.RN = CC.R
Where C.RN = 1
GROUP BY C.ID,C.Fund,C.RN,C.Dated )
select C.R,C.Fund,C.Dated,cc.Amt from CTE4 C INNER JOIN CTE3 CC
ON c.R = cc.R
declare #TableName table([Id] int, [Fund] varchar(1), [Date] datetime, [Amount] int)
declare #Sample table([SampleDate] datetime)
INSERT INTO #TableName
([Id], [Fund], [Date], [Amount])
VALUES
(1, 'A', '20150120 00:00:00', 250),
(2, 'A', '20150128 00:00:00', 300),
(3, 'A', '20150320 00:00:00', 400),
(4, 'A', '20150330 00:00:00', 200),
(5, 'B', '20150401 00:00:00', 500),
(6, 'B', '20150401 00:00:00', 600)
INSERT INTO #Sample ([SampleDate])
values ('20150128 00:00:00'), ('20150330 00:00:00'), ('20150401 00:00:00')
-- select * from #TableName
-- select * from #Sample
;WITH groups AS (
SELECT [Fund], [Date], [AMOUNT], MIN([SampleDate]) [SampleDate] FROM #TableName
JOIN #Sample ON [Date] <= [SampleDate]
GROUP BY [Fund], [Date], [AMOUNT])
SELECT [Fund], [SampleDate], SUM([AMOUNT]) FROM groups
GROUP BY [Fund], [SampleDate]
Explanation:
The CTE groups finds the earliest SampleDate which is later than (or equals to) your
data's date and enriches your data accordingly, thus giving them the group to be summed up in.
After that, you can group on the derived date.
I am trying to implement a paging routine that's a little different.
For the sake of a simple example, let's assume that I have a table defined and populated as follows:
DECLARE #Temp TABLE
(
ParentId INT,
[TimeStamp] DATETIME,
Value INT
);
INSERT INTO #Temp VALUES (1, '1/1/2013 00:00', 6);
INSERT INTO #Temp VALUES (1, '1/1/2013 01:00', 7);
INSERT INTO #Temp VALUES (1, '1/1/2013 02:00', 8);
INSERT INTO #Temp VALUES (2, '1/1/2013 00:00', 6);
INSERT INTO #Temp VALUES (2, '1/1/2013 01:00', 7);
INSERT INTO #Temp VALUES (2, '1/1/2013 02:00', 8);
INSERT INTO #Temp VALUES (3, '1/1/2013 00:00', 6);
INSERT INTO #Temp VALUES (3, '1/1/2013 01:00', 7);
INSERT INTO #Temp VALUES (3, '1/1/2013 02:00', 8);
TimeStamp will always be the same interval, e.g. daily data, 1 hour data, 1 minute data, etc. It will not be mixed.
For reporting and presentation purposes, I want to implement paging that:
Orders by TimeStamp
Starts out using a suggested pageSize (say 4), but will automatically adjust to include additional records matching on TimeStamp. In other words, if 1/1/2013 01:00 is included for one ParentId, the suggested pageSize will be overridden and all records for hour 01:00 will be included for all ParentId's. It's almost like the TOP WITH TIES option.
So running this query with pageSize of 4 would return 6 records. There are 3 hour 00:00 and 1 hour 01:00 by default, but because there are more hour 01:00's, the pageSize would be overridden to return all hour 00:00 and 01:00.
Here's what I have so far, and I think I'm close as it works for the first iteration, but sequent queries for the next pageSize+ rows doesn't work.
WITH CTE AS
(
SELECT ParentId, [TimeStamp], Value,
RANK() OVER(ORDER BY [TimeStamp]) AS rnk,
ROW_NUMBER() OVER(ORDER BY [TimeStamp]) AS rownum
FROM #Temp
)
SELECT *
FROM CTE
WHERE (rownum BETWEEN 1 AND 4) OR (rnk BETWEEN 1 AND 4)
ORDER BY TimeStamp, ParentId
The ROW_NUMBER ensures the minimum pageSize is met, but the RANK will include additional ties.
declare #Temp as Table ( ParentId Int, [TimeStamp] DateTime, [Value] Int );
insert into #Temp ( ParentId, [TimeStamp], [Value] ) values
(1, '1/1/2013 00:00', 6),
(1, '1/1/2013 01:00', 7),
(1, '1/1/2013 02:00', 8),
(2, '1/1/2013 00:00', 6),
(2, '1/1/2013 01:00', 7),
(2, '1/1/2013 02:00', 8),
(3, '1/1/2013 00:00', 6),
(3, '1/1/2013 01:00', 7),
(3, '1/1/2013 02:00', 8);
declare #PageSize as Int = 4;
declare #Page as Int = 1;
with Alpha as (
select ParentId, [TimeStamp], Value,
Rank() over ( order by [TimeStamp] ) as Rnk,
Row_Number() over ( order by [TimeStamp] ) as RowNum
from #Temp ),
Beta as (
select Min( Rnk ) as MinRnk, Max( Rnk ) as MaxRnk
from Alpha
where ( #Page - 1 ) * #PageSize < RowNum and RowNum <= #Page * #PageSize )
select A.*
from Alpha as A inner join
Beta as B on B.MinRnk <= A.Rnk and A.Rnk <= B.MaxRnk
order by [TimeStamp], ParentId;
EDIT:
An alternative query that assigns page numbers as it goes, so that next/previous page can be implemented without overlapping rows:
with Alpha as (
select ParentId, [TimeStamp], Value,
Rank() over ( order by [TimeStamp] ) as Rnk,
Row_Number() over ( order by [TimeStamp] ) as RowNum
from #Temp ),
Beta as (
select ParentId, [TimeStamp], Value, Rnk, RowNum, 1 as Page, 1 as PageRow
from Alpha
where RowNum = 1
union all
select A.ParentId, A.[TimeStamp], A.Value, A.Rnk, A.RowNum,
case when B.PageRow >= #PageSize and A.TimeStamp <> B.TimeStamp then B.Page + 1 else B.Page end,
case when B.PageRow >= #PageSize and A.TimeStamp <> B.TimeStamp then 1 else B.PageRow + 1 end
from Alpha as A inner join
Beta as B on B.RowNum + 1 = A.RowNum
)
select * from Beta
option ( MaxRecursion 0 )
Note that recursive CTEs often scale poorly.
I think your strategy of using row_number() and rank() is overcomplicating things.
Just pick the top 4 timestamps from the data. Then choose any timestamps that match those:
select *
from #temp
where [timestamp] in (select top 4 [timestamp] from #temp order by [TimeStamp])