I need help to create one script where i got stuck.
MemberId BeginDate EndDate Output
1039725910 3/1/2014 8/10/2014 0 End on 10th August
1039725910 8/11/2014 11/10/2014 1 Start on 11th August, 1 day gap
1039725910 11/11/2014 12/31/2014 1 Start on 11th August, 1 day gap
1166164140 1/1/2014 4/30/2039 0 End on 30 April
1166164140 2/5/2014 12/30/2039 2 Start on 1st May, Here is a 2 days gap
Here For one member I have three different begin and end date. for the first records for each member, it would be 0, for the 2nd records, the gap would be (2nd Begindate - 1st EndDate). For 3rd record, The difference would be (3rd Begin date - 2nd EndDate) and so on...I am not able to attach any screenshot.
Kindly help me on this.
Regards,
Ratan
You can use the row_number() window function together with a self-join to access the previous row partitioned by MemberId like this:
select
a.MemberId,
a.BeginDate,
a.EndDate,
Output = ISNULL(DATEDIFF(DAY, isnull(b.EndDate, a.BeginDate), a.BeginDate), 0)
from
(select *, rn = ROW_NUMBER() over (partition by memberid order by begindate) from members) a
left join
(select *, rn = ROW_NUMBER() over (partition by memberid order by begindate) from members) b
on a.MemberId = b.MemberId and a.rn - 1 = b.rn
With your sample data this would give you:
MemberId BeginDate EndDate Output
1039725910 2014-03-01 2014-08-10 0
1039725910 2014-08-11 2014-11-10 1
1039725910 2014-11-11 2014-12-31 1
1166164140 2014-01-01 2039-04-30 0
1166164140 2014-05-02 2039-12-30 -9129
If you need to disregard the year component you'll have to do some date arithmetic.
You can use ROW_NUMBER()
Try using query like one given below:
select *,
case when rno = 1 then 0
else datediff(day, begindate,enddate) end as difference
from
(select *, row_number() over (partition by MemberId order by MemberId) as rno from members)
tbl
Check below demo code:
SQLFiddle Demo
Related
I am trying to select customers who have spent amount less than 15 in two consecutive occasions, first purchase must be less than 15, second purchase must be less than 15 and must be 90 days or more after the first purchase. I manage to get those but not able to isolate two consecutive dates with amounts less than 15.
Ideally, only cust1 should appear as my result because even though event on 2010-01-01 violated the rule, another event on 2011-12-18 is preceded by an event that meets the requirement. On the other hand cust2 never had events with amount less than 15 in two consecutive occasions with second date being >= 90 days, so cust2 should not make my list.
#MyList table
customer
purchasedate
amount
customer
purchasedate
amount
cust1
2008-11-01
10
cust1
2010-01-01
25
cust1
2010-12-03
30
cust1
2010-12-25
22
cust1
2011-12-18
7
cust1
2011-12-24
11
cust1
2014-10-06
9
cust2
2010-01-01
11
cust2
2010-02-05
25
cust2
2013-10-17
8
cust2
2014-10-28
27
cust3
2010-01-01
6
cust3
2011-04-05
25
cust3
2013-01-01
8
cust3
2013-02-28
5
cust3
2013-04-05
12
My script below
WITH firstevent AS(
SELECT * FROM(
SELECT *,
row_number() OVER(PARTITION BY customer ORDER BY purchasedate ASC) rn
FROM #MyList
WHERE amount < 15) A
WHERE rn = 1
), secondevent AS (
SELECT * FROM(
SELECT *,
ROW_NUMBER() OVER(PARTITION BY customer ORDER BY purchasedate DESC) rn
FROM #MyList
WHERE amount < 15) B
WHERE rn = 1
)
SELECT f.customer, f.amount AS FirstAmount, s.amount AS LastAmount, f.purchasedate AS Date1,
s.purchasedate AS Date2
FROM firstevent f
INNER JOIN secondevent s ON (f.customer = s.customer)
WHERE DATEDIFF(D, f.purchasedate, s.purchasedate) >= 90
use LAG() to obtain the previous date and amount and compare
select *
from
(
select *,
prev_date = lag(purchasedate) over (partition by customer
order by purchasedate),
prev_amount = lag(amount) over (partition by customer
order by purchasedate)
from #MyList
) l
where l.amount < 15
and l.prev_amount < 15
and datediff(day, l.prev_date, l.purchasedate) >= 90
or using the row_number() method, perform a self join and compare
with list as
(
select *, rn = row_number() over (partition by customer order by purchasedate)
from #MyList
)
select *
from list l1
inner join list l2 on l1.customer = l2.customer
and l1.rn = l2.rn - 1
where l1.amount < 15
and l2.amount < 15
and datediff(day, l1.purchasedate, l2.purchasedate) >= 90
Is it possible to use the DATEADD function but exclude dates from a table?
We already have a table with all dates we need to exclude. Basically, I need to add number of days to a date but exclude dates within a table.
Example: Add 5 days to 01/08/2021. Dates 03/08/2021 and 04/08/2021 exist in the exclusion table. So, resultant date should be: 08/08/2021.
Thank you
A bit of a "wonky" solution, but it works. Firstly we use a tally to create a Calendar table of dates, that exclude your dates in the table, then we get the nth row, where n is the number of days to add:
DECLARE #DaysToAdd int = 5,
#StartDate date = '20210801';
WITH N AS(
SELECT N
FROM (VALUES(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL))N(N)),
Tally AS(
SELECT 0 AS I
UNION ALL
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS I
FROM N N1, N N2, N N3), --Up to 1,000
Calendar AS(
SELECT DATEADD(DAY,T.I, #StartDate) AS D,
ROW_NUMBER() OVER (ORDER BY T.I) AS I
FROM Tally T
WHERE NOT EXISTS (SELECT 1
FROM dbo.DatesTable DT
WHERE DT.YourDate = DATEADD(DAY,T.I, #StartDate)))
SELECT D
FROM Calendar
WHERE I = #DaysToAdd+1;
A best solution is probably a calendar table.
But if you're willing to traverse through every date, then a recursive CTE can work. It would require tracking the total iterations and another column to substract if any traversed date was in the table. The exit condition uses the total difference.
An example dataset would be:
CREATE TABLE mytable(mydate date); INSERT INTO mytable VALUES ('20210803'), ('20210804');
And an example function run in it's own batch:
ALTER FUNCTION dbo.fn_getDays (#mydate date, #daysadd int)
RETURNS date
AS
BEGIN
DECLARE #newdate date;
WITH CTE(num, diff, mydate) AS (
SELECT 0 AS [num]
,0 AS [diff]
,DATEADD(DAY, 0, #mydate) [mydate]
UNION ALL
SELECT num + 1 AS [num]
,CTE.diff +
CASE WHEN DATEADD(DAY, num+1, #mydate) IN (SELECT mydate FROM mytable)
THEN 0 ELSE 1 END
AS [diff]
,DATEADD(DAY, num+1, #mydate) [mydate]
FROM CTE
WHERE (CTE.diff +
CASE WHEN DATEADD(DAY, num+1, #mydate) IN (SELECT mydate FROM mytable)
THEN 0 ELSE 1 END) <= #daysadd
)
SELECT #newdate = (SELECT MAX(mydate) AS [mydate] FROM CTE);
RETURN #newdate;
END
Running the function:
SELECT dbo.fn_getDays('20210801', 5)
Produces output, which is the MAX(mydate) from the function:
----------
2021-08-08
For reference the MAX(mydate) is taken from this dataset:
n diff mydate
----------- ----------- ----------
0 0 2021-08-01
1 1 2021-08-02
2 1 2021-08-03
3 1 2021-08-04
4 2 2021-08-05
5 3 2021-08-06
6 4 2021-08-07
7 5 2021-08-08
You can use the IN clause.
To perform the test, I used a W3Schools Test DB
SELECT DATE_ADD(BirthDate, INTERVAL 10 DAY) FROM Employees WHERE FirstName NOT IN (Select FirstName FROM Employees WHERE FirstName LIKE 'N%')
This query shows all the birth dates + 10 days except for the only employee with name starting with N (Nancy)
I have a table with a column for ID, StartDate, EndDate, And whether or not there was a gap between the enddate of that row and the next start date. If there was only one set instance of that ID i know that I could just do
SELECT min(startdate),max(enddate)
FROM table
GROUP BY ID
However, I have multiple instances of these IDs in several non-connected timespans. So if I were to do that I would get the very first start date and the last enddate for a different set of time for that personID. How would I go about making sure I get the min a max dates for the specific blocks of time?
I thought about potentially creating a new column where it would have a number for each set of time. So for the first set of time that has no gaps, it would have 1, then when the next row has a gap it will add +1 corresponding to a new set of time. but I am not really sure how to go about that. Here is some sample data to illustrate what I am working with:
ID StartDate EndDate NextDate Gap_ind
001 1/1/2018 1/31/2018 2/1/2018 N
001 2/1/2018 2/30/2018 3/1/2018 N
001 3/1/2018 3/31/2018 5/1/2018 Y
001 5/1/2018 5/31/2018 6/1/2018 N
001 6/1/2018 6/30/2018 6/30/2018 N
This is a classic "gaps and islands" problem, where you are trying to define the boundaries of your islands, and which you can solve by using some windowing functions.
Your initial effort is on track. Rather than getting the next start date, though, I used the previous end date to calculate the groupings.
The innermost subquery below gets the previous end date for each of your date ranges, and also assigns a row number that we use later to keep our groupings in order.
The next subquery out uses the previous end date to identify which groups of date ranges go together (overlap, or nearly so).
The outermost query is the end result you're looking for.
SELECT
Grp.ID,
MIN(Grp.StartDate) AS GroupingStartDate,
MAX(Grp.EndDate) AS GroupingEndDate
FROM
(
SELECT
PrevDt.ID,
PrevDt.StartDate,
PrevDt.EndDate,
SUM(CASE WHEN DATEADD(DAY,1,PrevDt.PreviousEndDate) >= PrevDt.StartDate THEN 0 ELSE 1 END)
OVER (PARTITION BY PrevDt.ID ORDER BY PrevDt.RN) AS GrpNum
FROM
(
SELECT
ROW_NUMBER() OVER (PARTITION BY ID ORDER BY StartDate, EndDate) as RN,
ID,
StartDate,
EndDate,
LAG(EndDate,1) OVER (PARTITION BY ID ORDER BY StartDate) AS PreviousEndDate
FROM
tbl
) AS PrevDt
) AS Grp
GROUP BY
Grp.ID,
Grp.GrpNum;
Results:
+-----+------------------+--------------+
| ID | InitialStartDate | FinalEndDate |
+-----+------------------+--------------+
| 001 | 2018-01-01 | 2018-03-01 |
| 001 | 2018-05-01 | 2018-06-01 |
+-----+------------------+--------------+
SQL Fiddle demo.
Further reading:
The SQL of Gaps and Islands in Sequences
Gaps and Islands Across Date Ranges
This is an example of a gaps-and-islands problem. A simple solution is to use lag() to determine if there are overlaps. When there is none, you have the start of a group. A cumulative sum defines the group -- and you aggregate on that.
select t.id, min(startdate), max(enddate)
from (select t.*,
sum(case when prev_enddate >= dateadd(day, -1, startdate)
then 0 else 1
end) over (partition by id order by startdate) as grp
from (select t.*, lag(enddate) over (partition by id order by startdate) as prev_enddate
from t
) t
) t
group by id, grp;
I'm newish to SQL so sorry if the code is a little scruffy.
Basically I am creating a count of fire engines in use on every hour, which I have done, and that bit works. So I have a count of this for the past five years. Sorted.
But now I want to run it for a specific group of incidents (about 300 of them), showing how many engines were at that incident, every hour, and how many others were in use at the same time, but somewhere else.
My basic working code (that I modified from https://stackoverflow.com/a/43337534/5880512) is as follows. It just counts all P1 and P2 mobilisations at the defined time.
DECLARE #startdate datetime = '2018-05-03 00:00:00'
DECLARE #enddate datetime = '2018-05-05 00:00:00'
;with cte as
(
select #startdate startdate
union all
select DATEADD(minute, 60, startdate)
FROM cte
WHERE DATEADD(minute, 60, startdate) < #enddate
)
select convert(varchar(20), startdate, 120) as CreationTime, (select count(*) FROM MB_MOBILISATIONS WHERE MB_SEND < startdate and MB_LEAVE > startdate And (MB_CALL_SIGN Like '%P1' Or MB_CALL_SIGN Like '%P2')) as Count
from cte
option (maxrecursion 0)
To split these up for a particular incident, I can put the incident ref into the where clause, one as = so it will give me engines at that incident, and one as <> so it gives me the rest. This bit works too.
select convert(varchar(20), startdate, 120) as CreationTime, (select count(*) FROM MB_MOBILISATIONS WHERE MB_SEND < startdate and MB_LEAVE > startdate And (MB_CALL_SIGN Like '%P1' Or MB_CALL_SIGN Like '%P2') and MB_IN_REF = 1704009991) as 'At Incident'
, select convert(varchar(20), startdate, 120) as CreationTime, (select count(*) FROM MB_MOBILISATIONS WHERE MB_SEND < startdate and MB_LEAVE > startdate And (MB_CALL_SIGN Like '%P1' Or MB_CALL_SIGN Like '%P2') and MB_IN_REF <> 1704009991) as 'Other Incident'
The bit I can't work out to do, is to make this work for multiple incidents, without having to change the incident reference manually in the where clause for all 300.
The incident references I want to use will be stored in a temporary table. Ideally, I would like it to pick an ID, set the variables #startdate and #enddate, from the start and end of that incident, then do the hourly count for the duration of that incident.
Hopefully the results would look something like this
IncidentRef DateTime At Incident Other Incident
A 2018-05-03 1:00 4 2
A 2018-05-03 2:00 7 3
A 2018-05-03 3:00 5 3
A 2018-05-03 4:00 2 4
B 2017-03-01 9:00 7 2
B 2017-03-01 10:00 8 3
B 2017-03-01 11:00 6 1
B 2017-03-01 12:00 4 2
I hope that makes sense.
Thanks :)
Use something like this to limit the scope of your search to a smaller list. I've just added and referenced another CTE with a filter. If you're looking to parameterize the list you'll need a different approach like storing those id values in another table first.
with cte as (
select #startdate startdate
union all
select dateadd(minute, 60, startdate)
from cte
where dateadd(minute, 60, startdate) < #enddate
), mobi as (
select * from MB_MOBILISATIONS
where MB_IN_REF in (<insert list here>)
)
select convert(varchar(20), startdate, 120) as CreationTime, m."Count"
from cte cross apply (
select count(*) as "Count" from mobi
where MB_SEND < startdate and MB_LEAVE > startdate and
(MB_CALL_SIGN like '%P1' or MB_CALL_SIGN like '%P2')
) m;
I went ahead and rewrote your scalar subquery but I guess that's just a personal preference.
I have a table in MSSQL with the following structure:
PersonId
StartDate
EndDate
I need to be able to show the number of distinct people in the table within a date range or at a given date.
As an example i need to show on a daily basis the totals per day, e.g. if we have 2 entries on the 1st June, 3 on the 2nd June and 1 on the 3rd June the system should show the following result:
1st June: 2
2nd June: 5
3rd June: 6
If however e.g. on of the entries on the 2nd June also has an end date that is 2nd June then the 3rd June result would show just 5.
Would someone be able to assist with this.
Thanks
UPDATE
This is what i have so far which seems to work. Is there a better solution though as my solution only gets me employed figures. I also need unemployed on another column - unemployed would mean either no entry in the table or date not between and no other entry as employed.
CREATE TABLE #Temp(CountTotal int NOT NULL, CountDate datetime NOT NULL);
DECLARE #StartDT DATETIME
SET #StartDT = '2015-01-01 00:00:00'
WHILE #StartDT < '2015-08-31 00:00:00'
BEGIN
INSERT INTO #Temp(CountTotal, CountDate)
SELECT COUNT(DISTINCT PERSON.Id) AS CountTotal, #StartDT AS CountDate FROM PERSON
INNER JOIN DATA_INPUT_CHANGE_LOG ON PERSON.DataInputTypeId = DATA_INPUT_CHANGE_LOG.DataInputTypeId AND PERSON.Id = DATA_INPUT_CHANGE_LOG.DataItemId
LEFT OUTER JOIN PERSON_EMPLOYMENT ON PERSON.Id = PERSON_EMPLOYMENT.PersonId
WHERE PERSON.Id > 0 AND DATA_INPUT_CHANGE_LOG.Hidden = '0' AND DATA_INPUT_CHANGE_LOG.Approved = '1'
AND ((PERSON_EMPLOYMENT.StartDate <= DATEADD(MONTH,1,#StartDT) AND PERSON_EMPLOYMENT.EndDate IS NULL)
OR (#StartDT BETWEEN PERSON_EMPLOYMENT.StartDate AND PERSON_EMPLOYMENT.EndDate) AND PERSON_EMPLOYMENT.EndDate IS NOT NULL)
SET #StartDT = DATEADD(MONTH,1,#StartDT)
END
select * from #Temp
drop TABLE #Temp
You can use the following query. The cte part is to generate a set of serial dates between the start date and end date.
DECLARE #ViewStartDate DATETIME
DECLARE #ViewEndDate DATETIME
SET #ViewStartDate = '2015-01-01 00:00:00.000';
SET #ViewEndDate = '2015-02-25 00:00:00.000';
;WITH Dates([Date])
AS
(
SELECT #ViewStartDate
UNION ALL
SELECT DATEADD(DAY, 1,Date)
FROM Dates
WHERE DATEADD(DAY, 1,Date) <= #ViewEndDate
)
SELECT [Date], COUNT(*)
FROM Dates
LEFT JOIN PersonData ON Dates.Date >= PersonData.StartDate
AND Dates.Date <= PersonData.EndDate
GROUP By [Date]
Replace the PersonData with your table name
If startdate and enddate columns can be null, then you need to add
addditional conditions to the join
It assumes one person has only one record in the same date range
You could do this by creating data where every start date is a +1 event and end date is -1 and then calculate a running total on top of that.
For example if your data is something like this
PersonId StartDate EndDate
1 20150101 20150201
2 20150102 20150115
3 20150101
You first create a data set that looks like this:
EventDate ChangeValue
20150101 +2
20150102 +1
20150115 -1
20150201 -1
And if you use running total, you'll get this:
EventDate Total
2015-01-01 2
2015-01-02 3
2015-01-15 2
2015-02-01 1
You can get it with something like this:
select
p.eventdate,
sum(p.changevalue) over (order by p.eventdate asc) as total
from
(
select startdate as eventdate, sum(1) as changevalue from personnel group by startdate
union all
select enddate, sum(-1) from personnel where enddate is not null group by enddate
) p
order by p.eventdate asc
Having window function with sum() requires SQL Server 2012. If you're using older version, you can check other options for running totals.
My example in SQL Fiddle
If you have dates that don't have any events and you need to show those too, then the best option is probably to create a separate table of dates for the whole range you'll ever need, for example 1.1.2000 - 31.12.2099.
-- Edit --
To get count for a specific day, it's possible use the same logic, but just sum everything up to that day:
declare #eventdate date
set #eventdate = '20150117'
select
sum(p.changevalue)
from
(
select startdate as eventdate, 1 as changevalue from personnel
where startdate <= #eventdate
union all
select enddate, -1 from personnel
where enddate < #eventdate
) p
Hopefully this is ok, can't test since SQL Fiddle seems to be unavailable.