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I'm using Oracle 11g.
What I would like to do is select login data from the past (let's say) 10 hours. I would like to exclude the weekend from this, and let my query wrap around to the previous Friday. For example, if it's Monday at 8:00 AM, I want to be able to find the logins that occurred from 12-8 AM Monday, as well as data from 10-11:59 PM on Friday.
My current statement looks like this:
select * from logins where end_time >= sysdate - (10) / (24)
But I'm not sure how to exclude Saturday and Sunday.
I didn't see what Database as the Question was only tagged as SQL. Regardless the answer below is SQL Server but the concept will work in any database. I've used the method shown below in SQLite and Oracle.
Get a list of dates between two dates using a function
There is an excellent answer contained in the above SO Post I provided above. However this question has so many answers and the excepted answer is actually not the answer that solved my issue when I originally had a similar calendar table problem on my end.
I've pasted below the answer that works without having to create a calendar table and works within any standard query which can then be turned into a View/Stored Proc/Function etc.... And since the SQL below does not use a recursive CTE you can use this code in Views, Stored Procedures, Functions... etc... The dates table is still populated using a CTE but it does this using an exponential method of joining in several fake tables. I think it is brilliant and it performs well.
DECLARE #StartDate DATE = '08/01/2021'
, #EndDate Date = '08/01/2022'
;
-- From http://stackoverflow.com/questions/1378593/get-a-list-of-dates-between-two-dates-using-a-function
-- it basically just selects a whole bunch of 1s, gets the ROW_NUMBER() for each and filters.
-- This seems to perform better than inserting a bunch of rows in a WHILE loop or a recursive CTE
-- just UNIONing to the next date.
WITH
N0 AS (SELECT 1 AS n UNION ALL SELECT 1)
,N1 AS (SELECT 1 AS n FROM N0 t1, N0 t2)
,N2 AS (SELECT 1 AS n FROM N1 t1, N1 t2)
,N3 AS (SELECT 1 AS n FROM N2 t1, N2 t2)
,N4 AS (SELECT 1 AS n FROM N3 t1, N3 t2)
,N5 AS (SELECT 1 AS n FROM N4 t1, N4 t2)
,N6 AS (SELECT 1 AS n FROM N5 t1, N5 t2)
,nums AS (SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 1)) AS num FROM N6)
SELECT DATEADD(day, num - 1, #StartDate) AS TheDate
, DATENAME(WEEKDAY, (DATEADD(day, num - 1, #StartDate))) AS TheDayName
, num - 1 AS TheOffset
FROM nums
WHERE num <= DATEDIFF(day, #StartDate, #EndDate) + 1
In the above SQL I added the field for TheDayName so that you can filter out the weekends however you can add so many more fields that pull in more details of the dates being pulled in your query. Refer to the below SQL as it shows how to add all of the unique date parts into the CTE as needed. Again I added one of the below fields to the above CTE to pull TheDayName.
/* The below shows how to obtain additional information a date */
-- https://www.mssqltips.com/sqlservertip/4054/creating-a-date-dimension-or-calendar-table-in-sql-server/
DECLARE #d DATE = '07/26/21';
SELECT
TheDate = CONVERT(date, #d),
TheDay = DATEPART(DAY, #d),
TheDayName = DATENAME(WEEKDAY, #d),
TheWeek = DATEPART(WEEK, #d),
TheISOWeek = DATEPART(ISO_WEEK, #d),
TheDayOfWeek = DATEPART(WEEKDAY, #d),
TheMonth = DATEPART(MONTH, #d),
TheMonthName = DATENAME(MONTH, #d),
TheQuarter = DATEPART(Quarter, #d),
TheYear = DATEPART(YEAR, #d),
TheFirstOfMonth = DATEFROMPARTS(YEAR( #d), MONTH( #d ), 1),
TheLastOfYear = DATEFROMPARTS(YEAR( #d), 12, 31),
TheDayOfYear = DATEPART(DAYOFYEAR, #d)
Last if you are needing an example of how you JOIN back to a calendar table see the accepted answer in this SO Post: How to Calculate the Total Unique Days Employed for All Jobs - No overlap days counted twice
I have a table with 10 million rows, where there are two columns that contain the start date and the end date of the range. For example, 2019-09-25 and 2019-10-20. I want to extract the month number with the maximum number of days, in this example it will be 10. In addition to dates that are separated by one month, there are also such examples: 2019-07-01 and 2019-07-29 (within one month), as well as 2019-07-01 and 2019-09-05 (more than one month). How can I implement this?
Seems like you could do something like this:
SELECT CASE WHEN DATEDIFF(DAY, DATEFROMPARTS(YEAR(EndDate),MONTH(EndDate),1),EndDate) >= DATEDIFF(DAY, StartDate, EOMONTH(StartDate)) THEN DATEPART(MONTH,EndDate)
ELSE DATEPART(MONTH,StartDate)
END
FROM (VALUES('20190925','20191020'))V(StartDate,EndDate);
Does the following fit your requirements?
You can build a table of days-in-month (this would be permanent ideally)
and then join to it using the month numbers of your min and max dates.
declare #start date='20190925', #end date='20191020';
--declare #start date='20190701', #end date='20190729';
--declare #start date='20190701', #end date='20190905';
with dim as (
select m,DAY(DATEADD(DD,-1,DATEADD(mm, DATEDIFF(mm, 0, DateFromParts(Year(GetDate()),m,1) )+1, 0)))d
from (values(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12))m(m)
)
select top(1) with ties m
from dim
where m between Month(#start) and Month(#end)
order by d desc
You don't state how you determin the most days where there are several months with the same number of months, so with ties includes all qualifying months.
Edit
So I don't know if there is a requirement to span years - the sample data suggests not - however with a permanent list of dates and corresponding days in month values (this is often part of a calendar table) a slight tweak will accomodate it.
with dim as (
select Year(#start)*100 + m m, Day(DATEADD(DD,-1,DATEADD(mm, DATEDIFF(mm, 0, DateFromParts(Year(#start),m,1) )+1, 0)))d
from (values(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12))m(m)
union all
select Year(#end)*100 + m m, Day(DATEADD(DD,-1,DATEADD(mm, DATEDIFF(mm, 0, DateFromParts(Year(#end),m,1) )+1, 0)))d
from (values(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12))m(m)
)
select top(1) with ties m
from dim
where m between Year(#start)*100 + Month(#start) and Year(#end)*100 + Month(#end)
order by d desc
You could try something like this
with
l0(n) as (
select 1 n
from (values (1),(1),(1),(1),(1),(1),(1),(1)) as v(n))
select top(1) with ties
vTable.*, calc.dt month_with_most_days
from (values ('20190925','20191020'),
('20190925','20191120')) vTable(startdate, enddate)
cross apply (values (datediff(month, vTable.startdate, vTable.enddate))) diff(mo_count)
cross apply (select top (diff.mo_count+1)
row_number() over (order by (select null)) n
from l0 l1, l0 l2, l0 l3, l0 l4) tally /* 8^4 months possible */
cross apply (values (cast(case when tally.n=1 then startdate
when tally.n=diff.mo_count+1 then enddate
else eomonth(dateadd(month, tally.n-1, startdate)) end as date))) calc(dt)
order by row_number() over (partition by startdate, enddate
order by day(calc.dt) desc);
startdate enddate month_with_most_days
20190925 20191020 2019-09-25
20190925 20191120 2019-10-31
I'm trying to convert a 7 digit julian/mainframe date into a calendar date of format mmddyy in SQL Server.
An example of this being julian date 2005020, where the first 4 digits are the year, 2005, and the last three are the day number in a calendar, so 020 = january 20. So I'd need to get this date as 012005(MMDDYY) in SQL Server.
I've been using the following query but keep getting an error after it loads a few records:
SELECT DATEADD(day,CAST(RIGHT([julianDateColumn],3) as int)-,LEFT([julianDateColumn],4))
The error I've been getting:
Conversion failed when converting date and/or time from character string.
Originally I was doing this in an Access DB using the "DATESERIAL" function but from what I've seen the closest thing to that in SQL Server was "DATEFROMPARTS", I tried using the following formula but it also didn't work:
DATEFROMPARTS([julianDateColumn]/1000,1,[julianDateColumn] % 1000)
Thanks in advance!
The simplest would seem to be to take the left as the year, and the add the days (-1) to make a date. Also, rather than using a format of MMDDYY I'm going to go straight a date datatype. If you want it in a specific format, that's for your presentation layer.
SELECT JulianDate,
CONVERT(date,DATEADD(DAY,RIGHT(JulianDate,3)-1,CONVERT(datetime,LEFT(JulianDate,4)))) AS ActualDate --4 int strings are iterpreted as the year, so I'm going to take advantage of that
FROM (VALUES('2005020'))V(JulianDate);
Based on the comments on the answer, it appears that the OP has some dates that don't conform to the format that stated (yyyyddd). Therefore what we could use here is a calendar table, here, and then LEFT JOIN to it and see what bad rows you get (and INNER JOIN to get the dates).
You can create the table with something like this:
CREATE TABLE dbo.CalendarTable (CalendarDate date NOT NULL PRIMARY KEY,
CalenderYear AS DATEPART(YEAR, CalendarDate) PERSISTED,
CalenderMonth AS DATEPART(MONTH, CalendarDate) PERSISTED,
CalenderDay AS DATEPART(DAY, CalendarDate) PERSISTED,
CalenderMonthName AS DATENAME(MONTH, CalendarDate),
JulianDate AS DATEPART(YEAR,CalendarDate) * 1000 + DATEDIFF(DAY,DATEFROMPARTS(DATEPART(YEAR, CalendarDate),1,1),CalendarDate) + 1 PERSISTED); --Some example columns
WITH N AS(
SELECT N
FROM (VALUES(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL))N(N)),
Tally AS(
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) -1 AS I
FROM N N1, N N2, N N3, N N4, N N5, N N6),
Dates AS(
SELECT CONVERT(date,DATEADD(DAY, T.I, '19000101')) AS CalendarDate
FROM Tally T)
INSERT INTO dbo.CalendarTable(CalendarDate)
SELECT CalendarDate
FROM Dates
WHERE CalendarDate < '21000101';
GO
Then we can do something like this to get the bad rows:
SELECT YT.JulianDate
FROM dbo.YourTable YT
LEFT JOIN dbo.CalendarTable CT ON YT.JulianDate = CT.JulianDate
WHERE CT.JulianDate IS NULL;
I think I would use datefromparts() and dateadd():
select dateadd(day,
right(juliandate, 3) - 1),
datefromparts(left(juliandate, 4), 1, 1)
)
select Format(cast(concat(substring('2005020', 1, 4), '-', Month(cast(substring('2005020', 5, len('2005020')) as int)) ,'-', day(dateadd(day,-1,cast(substring('2005020', 5, len('2005020')) as int ) ) )) as date), 'MMddyy')
Currently I'm trying to join a date table to a ledger table so I can fill the gaps of the ledger table whenever there are no transactions in certain instances (e.g. there are transactions on March 1st and in March 3rd, but no transaction in March 2nd. And by joining both tables March 2nd would appear in the ledger table but with 0 for the variable we're analyzing.)
The challenge is that I can't create a Date object/table/dimension because I don't have permissions to create tables in the database. Therefore I've been generating a date sequence with this code:
DECLARE #startDate date = CAST('2016-01-01' AS date),
#endDate date = CAST(GETDATE() AS date);
SELECT DATEADD(day, number - 1, #startDate) AS [Date]
FROM (
SELECT ROW_NUMBER() OVER (
ORDER BY n.object_id
)
FROM sys.all_objects n
) S(number)
WHERE number <= DATEDIFF(day, #startDate, #endDate) + 1;
So, is there the possibility to join both tables into the same statement? Let's say the ledger table looks like this:
SELECT
date,cost
FROM ledger
I'd assume it can be done by using a subquery but I don't know how.
Thank you.
There is a very good article by Aaron Bertrand showing several methods for generating a sequence of numbers (or dates) in SQL Server: Generate a set or sequence without loops – part 1.
Try them out and see for yourself which is faster or more convenient to you. (spoiler - Recursive CTE is rather slow)
Once you've picked your preferred method you can wrap it in a CTE (common-table expression).
Here I'll use your method from the question
WITH
CTE_Dates
AS
(
SELECT
DATEADD(day, number - 1, #startDate) AS dt
FROM (
SELECT ROW_NUMBER() OVER (
ORDER BY n.object_id
)
FROM sys.all_objects n
) S(number)
WHERE number <= DATEDIFF(day, #startDate, #endDate) + 1
)
SELECT
...
FROM
CTE_Dates
LEFT JOIN Ledger ON Ledger.dt = CTE_Dates.dt
;
You can use your generated date sequence as a CTE and LEFT JOIN that to your ledger table. For example:
DECLARE #startDate date = CAST('2020-02-01' AS date);
DECLARE #endDate date = CAST(GETDATE() AS date);
WITH dates AS (
SELECT DATEADD(day, number - 1, #startDate) AS [Date]
FROM (
SELECT ROW_NUMBER() OVER (
ORDER BY n.object_id
)
FROM sys.all_objects n
) S(number)
WHERE number <= DATEDIFF(day, #startDate, #endDate) + 1
)
SELECT dates.Date, COALESCE(ledger.cost, 0)
FROM dates
LEFT JOIN (VALUES ('2020-02-02', 14), ('2020-02-05', 10)) AS ledger([Date], [cost]) ON dates.Date = ledger.Date
Output:
Date cost
2020-02-01 0
2020-02-02 14
2020-02-03 0
2020-02-04 0
2020-02-05 10
2020-02-06 0
Demo on dbfiddle
I have this data:
id worked_date
-----------------
1 2013-09-25
2 2013-09-26
3 2013-10-01
4 2013-10-04
5 2013-10-07
I want to add a column called weekCount. The based date is 2013-09-25. So all the data with worked_date from 2013-09-25 to 2013-10-01 will have weekCount as 1 and from 2013-10-02 to 2013-10-8 will have weekCount as 2 and so on. How can that be done?
Thanks.
Here's one way using DATEDIFF:
select id,
worked_date,
1 + (datediff(day, '2013-09-25', worked_date) / 7) weekCount
from yourtable
SQL Fiddle Demo
Perhaps an approach like this will solve your problem.
I compute an in-memory table that contains the week's boundaries along with a monotonically increasing number (BuildWeeks). I then compare my worked_date values to my date boundaries. Based on your comment to #sgeddes, you need the reverse week number so I then use a DENSE_RANK function to calculate the ReverseWeekNumber.
WITH BOT(StartDate) AS
(
SELECT CAST('2013-09-25' AS date)
)
, BuildWeeks (WeekNumber, StartOfWeek, EndOfWeek) AS
(
SELECT
N.number AS WeekNumber
, DateAdd(week, N.number -1, B.StartDate) AS StartOfWeek
, DateAdd(d, -1, DateAdd(week, N.number, B.StartDate)) AS EndOfWeek
FROM
dbo.Numbers AS N
CROSS APPLY
BOT AS B
)
SELECT
M.*
, BW.*
, DENSE_RANK() OVER (ORDER BY BW.WeekNumber DESC) AS ReverseWeekNumber
FROM
dbo.MyTable M
INNER JOIN
BuildWeeks AS BW
ON M.worked_date BETWEEN BW.StartOfWeek ANd BW.EndOfWeek
;
SQLFiddle
If you are looking for a Fiscal Week number, I would use a function that would calculate the week:
CREATE FUNCTION FiscalWeek(#FiscalStartDate datetime, #EvalDate datetime)
RETURNS INT
AS
BEGIN
DECLARE #weekNumber INT = (DATEDIFF(DAY, #FiscalStartDate, #EvalDate) / 7) + 1
RETURN (#weekNumber % 52)
END
GO
If you used a fiscal starting date of '2013-09-25' and an evaluation date of '2014-09-25' you would get a week number of 1.
Using a function gives you a little more flexibility to do whatever you need.
Perhaps not the most elegant way but this works for me to get the top rank number:
WITH CTE AS (
SELECT employee_id, DENSE_RANK() OVER (ORDER BY DATEDIFF(DAY, ''20130925'', worked_date )/7 DESC) AS weekRank
FROM Timesheet
)
SELECT TOP (1) weekRank
FROM CTE
WHERE employee_id=#employee_id
ORDER BY weekRank DESC
This is how I can create weekRank column and pass a parameter dynamically:
WITH rank_cte AS (
SELECT timesheet_id,employee_id, date_worked,
dateadd(week, datediff(day,'20000105',worked_date) / 7, '20000105') AS WeekStart,
dateadd(week, datediff(day,'20000105',worked_date) / 7, '20000105')+6 AS WeekEnd,
DENSE_RANK() OVER (ORDER BY 1 + DATEDIFF(DAY, '20130925', worked_date )/7 DESC) AS weekRank
FROM Timesheet
)
SELECT timesheet_id, worked_date, WeekStart, WeekEnd, weekRank
FROM rank_cte rc
WHERE employee_id=#employee_id
AND weekRank=#weekRank
ORDER BY worked_date DESC
Thanks