I have the following
id eventid startdate enddate
1 1 2009-01-03 2009-01-05
1 2 2009-01-05 2009-01-09
1 3 2009-01-12 2009-01-15
How to generate the missing dates pertaining to every eventid?
Edit:
The missing gaps are to be find out based on the eventid's. e.g. for eventid 1 the output should be 1/3/2009,1/4/2009,1/5/2009.. for eventtype id 2 it will be 1/5/2009, 1/6/2009... to 1/9/2009 etc
My task is to find out the missing dates between two given dates.
Here is the whole thing which i have done so far
declare #tblRegistration table(id int primary key,startdate date,enddate date)
insert into #tblRegistration
select 1,'1/1/2009','1/15/2009'
declare #tblEvent table(id int,eventid int primary key,startdate date,enddate date)
insert into #tblEvent
select 1,1,'1/3/2009','1/5/2009' union all
select 1,2,'1/5/2009','1/9/2009' union all
select 1,3,'1/12/2009','1/15/2009'
;with generateCalender_cte as
(
select cast((select startdate from #tblRegistration where id = 1 )as datetime) DateValue
union all
select DateValue + 1
from generateCalender_cte
where DateValue + 1 <= (select enddate from #tblRegistration where id = 1)
)
select DateValue as missingdates from generateCalender_cte
where DateValue not between '1/3/2009' and '1/5/2009'
and DateValue not between '1/5/2009' and '1/9/2009'
and DateValue not between '1/12/2009'and'1/15/2009'
Actually what I am trying to do is that, I have generated a calender table and from there I am trying to find out the missing dates based on the id's
The ideal output will be
eventid missingdates
1 2009-01-01 00:00:00.000
1 2009-01-02 00:00:00.000
3 2009-01-10 00:00:00.000
3 2009-01-11 00:00:00.000
and also it has to be in SET BASED and the start and end dates should not be hardcoded
Thanks in adavnce
The following uses a recursive CTE (SQL Server 2005+):
WITH dates AS (
SELECT CAST('2009-01-01' AS DATETIME) 'date'
UNION ALL
SELECT DATEADD(dd, 1, t.date)
FROM dates t
WHERE DATEADD(dd, 1, t.date) <= '2009-02-01')
SELECT t.eventid, d.date
FROM dates d
JOIN TABLE t ON d.date BETWEEN t.startdate AND t.enddate
It generates dates using the DATEADD function. It can be altered to take a start & end date as parameters. According to KM's comments, it's faster than using the numbers table trick.
Like rexem - I made a function that contains a similar CTE to generate any series of datetime intervals you need. Very handy for summarizing data by datetime intervals like you are doing.
A more detailed post and the function source code are here:
Insert Dates in the return from a query where there is none
Once you have the "counts of events by date" ... your missing dates would be the ones with a count of 0.
Related
I'm having trouble writing a recursive function that would count the number of active clients on any given day.
Say I have a table like this:
Client
Start Date
End Date
1
1-Jan-22
2
1-Jan-22
3-Jan-22
3
3-Jan-22
4
4-Jan-22
5-Jan-22
5
4-Jan-22
6-Jan-22
6
7-Jan-22
9-Jan-22
I want to return a table that would look like this:
Date
NumActive
1-Jan-22
2
2-Jan-22
2
3-Jan-22
3
4-Jan-22
4
5-Jan-22
4
6-Jan-22
3
7-Jan-22
3
8-Jan-22
3
9-Jan-22
4
Is there a way to do this? Ideally, I'd have a fixed start date and go to today's date.
Some pieces I have tried:
Creating a recursive date table
Truncated to Feb 1, 2022 for simplicity:
WITH DateDiffs AS (
SELECT DATEDIFF(DAY, '2022-02-02', GETDATE()) AS NumDays
)
, Numbers(Numbers) AS (
SELECT MAX(NumDays) FROM DateDiffs
UNION ALL
SELECT Numbers-1 FROM Numbers WHERE Numbers > 0
)
, Dates AS (
SELECT
Numbers
, DATEADD(DAY, -Numbers, CAST(GETDATE() -1 AS DATE)) AS [Date]
FROM Numbers
)
I would like to be able to loop over the dates in that table, such as by modifying the query below for each date, such as by #loopdate. Then UNION ALL it to a larger final query.
I'm now stuck as to how I can run the query to count the number of active users:
SELECT
COUNT(Client)
FROM clients
WHERE [Start Date] >= #loopdate AND ([End Date] <= #loopdate OR [End Date] IS NULL)
Thank you!
You don't need anything recursive in this particular case, you need as a minimum a list of dates in the range you want to report on, ideally a permanent calendar table.
for purposes of demonstration you can create something on the fly, and use it like so, with the list of dates something you outer join to:
with dates as (
select top(9)
Convert(date,DateAdd(day, -1 + Row_Number() over(order by (select null)), '20220101')) dt
from master.dbo.spt_values
)
select d.dt [Date], c.NumActive
from dates d
outer apply (
select Count(*) NumActive
from t
where d.dt >= t.StartDate and (d.dt <= t.EndDate or t.EndDate is null)
)c
See this Demo Fiddle
I have 2 dates, StartDate and EndDate:
Declare #StartDate date='2018/01/01', #Enddate date ='2018/12/31'
Then there is some data with a date and value in a mytable table:
----------------------------
ID date value
----------------------------
1 2018/02/14 4
2 2018/09/26 7
3 2017/09/20 2
data maybe start before 2018 and if it exist before #startdate get before values
else get 0
I'm looking to get a result that looks like this:
-----------------------------------
fromdate todate value
-----------------------------------
2018/01/01 2018/02/13 2
2018/02/14 2018/09/25 4
2018/09/26 2018/12/31 7
The first fromdate comes from #StartDate and the last todate is from #Enddate, and the other data should be generated.
I'm hoping to get this in an SQL query. I use sql-server 2016
You could use a CTE to create your full range of dates, and then LEAD to create the ToDate column:
DECLARE #FromDate date = '20180101',
#ToDate date = '20181231';
WITH VTE AS(
SELECT ID,
CONVERT(date,[date]) [date], --This is why using keywords for column names is a bad idea
[value]
FROM (VALUES(1,'20180214',4),
(2,'20180926',7),
(3,'20170314',4))V(ID,[date],[value])),
Dates AS(
SELECT [date]
FROM VTE V
WHERE V.[date] BETWEEN #FromDate and #ToDate
UNION ALL
SELECT [date]
FROM (VALUES(#FromDate))V([date]))
SELECT D.[date] AS FromDate,
LEAD(DATEADD(DAY, -1,D.[date]),1,#ToDate) OVER (ORDER BY D.[date]) AS ToDate,
ISNULL(V.[value],0) AS [value]
FROM Dates D
LEFT JOIN VTE V ON D.[date] = V.[date];
db<>fiddle
with cte as
(
select 0 as row_num, #StartDate as start_date, 0 as val
UNION
select ROW_NUMBER() OVER(ORDER BY start_date) as row_num, * from input
)
select curr.start_date
, DATEADD(day,-1,ISNULL(nex.start_date,DATEADD(day,1,#Enddate))) as end_date
, curr.val
from cte curr
left join cte nex on curr.row_num = nex.row_num - 1;
You can find the simulation here: https://rextester.com/EIAXW23839
I have a table with the following structure:
ID: StartDate: EndDate
I want to show all dates in the date range for each ID.
Eg
ID = 1: StartDate = 01/01/2018: EndDate = 03/01/2018
ID: 1 01/01/2018
ID: 1 02/01/2018
ID: 1 03/01/2018
I think i need to use a cross join but im unsure how to create this for multiple rows?
Here is the CTE for SQL Server, the syntax is somewhat different:
declare #startdate date = '2018-01-01';
declare #enddate date = '2018-03-18';
with
dates as (
select #startdate as [date]
union all
select dateadd(dd, 1, [date]) from dates where [date] < #enddate
)
select [date] from dates
So i ended up using a date table and just cross referencing that
select *
from Date d
inner join WorkingTable w
on d.Date >= w.StartDate
and d.date < w.EndDate
In standard SQL you can use a recursive CTE:
with recursive dates as (
select date '2018-01-01' as dte
union all
select dte + interval '1 day'
from dates
where dte < date '2018-01-03'
)
select dte
from dates;
The exact syntax (whether recursive is needed and date functions) differ among databases. Not all databases support this standard functionality.
Now got this for only one id..,
create table #dateTable(id int, col1 date, col2 date)
insert into #dateTable values(1,'05-May-2018','08-May-2018') ,(2,'05-May-2018','05-May-2018')
select *from #dateTable
with cte(start, ends) as(
select start = (select top 1 col1 from #dateTable), ends = (select top 1 col2 from #dateTable)
union all
select DATEADD(dd,1,start),ends from cte where start <> ends
)select start from cte option (maxrecursion 10)
I'm still working... I update soon...!
I'd like to create a table that has one column and the column is weekly dates starting with 1/1/2015 thru the end of 2015. Is there an easy way to do this?
ie
CREATE TABLE Week_End_Dates
(
WeekEndDt date
);
INSERT INTO Week_End_Dates(WeekEndDt)
VALUES ('2015-01-01'),('2015-01-08')
There are plenty of ways to generate a date sequence. One is to use a common table expression like this:
WITH CTE (DT) AS
(
SELECT CAST('2015-01-01' AS DATE) DT
UNION ALL
SELECT DATEADD(WEEK, 1, DT)
FROM CTE
WHERE DATEADD(WEEK, 1, DT) < '2016-01-01'
)
INSERT INTO Week_End_Dates(WeekEndDt)
SELECT * FROM CTE
It's not the most efficient (and can easily be optimized in several ways), but it should do what you seem to want.
The query would generate a result like:
WeekEndDt
2015-01-01
2015-01-08
2015-01-15
2015-01-22
2015-01-29
... etc until 2015-12-31
How can I enumerate multiple date ranges in SQL Server 2008? I know how to do this if my table contains a single record
StartDate EndDate
2014-01-01 2014-01-03
;WITH DateRange
AS (
SELECT #StartDate AS [Date]
UNION ALL
SELECT DATEADD(d, 1, [Date])
FROM DateRange
WHERE [Date] < #EndDate
)
SELECT * FROM DateRange
OUTPUT
2014-01-01, 2014-01-02, 2014-01-03
I am however lost as how to do it if my table contains multiple records. I could possibly use the above logic in a cursor but want to know if there is a set based solution instead.
StartDate EndDate
2014-01-01 2014-01-03
2014-01-05 2014-01-06
DESIRED OUTPUT:
2014-01-01, 2014-01-02, 2014-01-03, 2014-01-05, 2014-01-06
Well, let's see. Define the ranges as a table. Then generate the full range of dates from the first to the last date. Finally, select the dates that are in the range:
with dateranges as (
select cast('2014-01-01' as date) as StartDate, cast('2014-01-03' as date) as EndDate union all
select '2014-01-05', '2014-01-06'
),
_dates as (
SELECT min(StartDate) AS [Date], max(EndDate) as enddate
FROM dateranges
UNION ALL
SELECT DATEADD(d, 1, [Date]), enddate
FROM _dates
WHERE [Date] < enddate
),
dates as (
select [date]
from _dates d
where exists (select 1 from dateranges dr where d.[date] >= dr.startdate and d.[date] <= dr.enddate)
)
select *
from dates
. . .
You can see this work here.
You could grab the min and max dates first, like so:
SELECT #startDate = MIN(StartDate), #endDate = MAX(EndDate)
FROM YourTable
WHERE ...
And then pass those variables into your date range enumerator.
Edit... Whoops, I missed an important requirement. See the accepted answer.
As GordonLinoff mentioned, you should:
Store your ranges in a table
Generate a range of dates that encompasses your ranges
Filter down to only those dates that fall within the range
The following query builds up a collection of numbers, and then uses that to quickly generate all of the dates that fall within each range.
-- Create a table of digits (0-9)
DECLARE #Digits TABLE (digit INT NOT NULL PRIMARY KEY);
INSERT INTO #Digits(digit)
VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
WITH
-- Store our ranges in a common table expression
CTE_DateRanges(StartDate, EndDate) AS (
SELECT '2014-01-01', '2014-01-03'
UNION ALL
SELECT '2014-01-05', '2014-01-06'
)
SELECT DATEADD(DAY, NUMBERS.num, RANGES.StartDate) AS Date
FROM
(
-- Create the list of all 3-digit numbers (0-999)
SELECT D3.digit * 100 + D2.digit * 10 + D1.digit AS num
FROM #Digits AS D1
CROSS JOIN #Digits AS D2
CROSS JOIN #Digits AS D3
-- Add more CROSS JOINs to #Digits if your ranges span more than 999 days
) NUMBERS
-- Join to our ranges table to generate the dates and filter them
-- down to those that fall within a range
INNER JOIN CTE_DateRanges RANGES
ON DATEADD(DAY, NUMBERS.num, RANGES.StartDate) <= RANGES.EndDate
ORDER BY
Date
The date creation is done by joining our number list with our date ranges, using the number as a number of days to add to the StartDate of the range. We then filter out any results where the generated date for a given range falls beyond that range's EndDate. Since we're adding a non-negative number of days to the StartDate to generate the date, we know that our date will always be greater-than-or-equal-to the StartDate of the range, so we don't need to include StartDate in the WHERE clause.
This query will return DATETIME values. If you need a DATE value, rather than a DATETIME value, you can simply cast the value in the SELECT clause.
Credit goes to Itzik Ben-Gan for the digits table.