How do I change the syntax datepart(week,[Tran Date]) as WeekNum to provide the week number based on a Mon-Sun week standard vs. Sun-Sat?
For example: I need Sun 2/13/2023 to report week number 6 and not week number 7.
I'm open to suggestions.
It should be a setting in SSMS:
https://database.guide/set-datefirst-set-the-first-day-of-the-week-in-sql-server/
you need to set the DATEFORST to one see example
SET DATEFIRST 1;
SELECT ##DATEFIRST AS 'First Day'
,DATEPART(dw, SYSDATETIME()) AS 'Today'
,DATEPART(dw, '2023-02-19') AS 'Sunday';
First Day
Today
Sunday
1
3
7
fiddle
Related
Consider the date "2022-07-02"
For the month July first week only have 3 days in it.
I need to find the number of days in the week for the given date.
In above date the week has 3 days where "2022-07-02" day reside.
Example 2 :
For month June in 2022 first week has 5 days in the week
Therefore if i declare a date as "2022-06-03" it should pass the number of days in the week as 5
I need a query to find the number of days for the specific week.
set datefirst 1 -- assumes Monday is set as start of week
declare #myDate date = getdate();
-- calculate the next last day of week
declare #nextSunday date = dateadd(day, 7 - datepart(weekday, #myDate), #myDate);
select case
-- advancing into the next month implies a partial week
-- datediff(month, #myDate, nextSunday) = 1 would be equivalent
when day(#nextSunday) < day(#myDate) then 7 - day(#nextSunday)
-- else see if still within first week
when day(#nextSunday) < 7 then day(#nextSunday)
else 7 end;
Within a query you might use it this way:
select case
when day(nextSunday) < day(dateColumn) then 7 - day(nextSunday)
when day(nextSunday) < 7 then day(nextSunday)
else 7 end
from
myData cross apply (
values (dateadd(day, 7 - datepart(weekday, dateColumn), dateColumn))
) v(nextSunday);
https://dbfiddle.uk/?rdbms=sqlserver_2019&fiddle=ee5bfb52dabe31dd619cfd136689db59
If you don't want the shorthand form then just replace every instance of nextSunday in the final step with its full expression.
There's nothing in the logic that prevents this from working with another first day of week. I just chose a variable name that helped ellucidate this particular problem.
I need some help in writing an SQL in SQL Server where I need to count number of rows group by weeks. There is a tricky description of week which is following
- For any date before 08/13/2015 the week is of 7 days (i.e. from Thu through Wed)
- For date 08/13/2015 the week is consider a 9 day week (i.e. from Thursday through Friday so its between 08/13/2015 through 08/21/2015)
- For date 08/22/2015 the week is back to 7 days (i.e. Sat through Friday)
Now having said all the above the result I want to see in my report is the following way . NOTE: WE column in the below attached image is the last day of the week for the range.
Sample Result Image
Just write a case statement for the 3 different options. You can find the start day with something like this:
DATEADD(week, DATEDIFF(day, 3,getdate()) / 7, 3) -- Thursdays
DATEADD(week, DATEDIFF(day, 5,getdate()) / 7, 5) -- Saturdays
The numbers 3 and 5 come from the fact that day 0 (=1.1.1900) is Monday.
If you use this a lot, it might be a good idea to write a inline table valued function to return the dates you need.
Is there a way to get the week number of a date with SQL that is database independent?
For example to get the month of a date I use:
SELECT EXTRACT(MONTH FROM :DATE)
But the EXTRACT function doesn't know about weeks in SQL92.
Please pay attention to the fact that I want a solution that is database independent! Do not misinterpret this as a question regarding MS SQL Server.
There doesn't appear to be a single standard SQL function to extract the week number from a date - see here for a comparison of how different SQL dialects can extract different dateparts from date fields.
You can try this.
declare #date datetime
select #date='2013-03-15 00:00:00'
select 'Week No: '+ convert(varchar(10),datepart(wk,#date)) as weekno
Try this one :
SELECT DATENAME(yy,GETDATE())+RIGHT(DATENAME(wk,GETDATE()),2)
To understand DATENAME, please follow this link : sqltutorials.blogspot.be/2007/05/sql-datename.html and for the right, suite101.com/article/sql-functions-leftrightsubstrlengthcharindex-a209089 . There are examples to better understand ;-) It will work on MS and other sql servers normally ;-)
The only db independent solution I see is to get the number of days between today and Jan 1 of curr. year. Then divide it by 7 and round it up. There is 73 days from Jan 1 till today, which gives 10.43 as week number. The ISO week number is 11.
Correction: the number of days between last day of the current week and Jan 1 of curr. year. In this case the ISO week is 10, and 68/7 = 10 (rounded).
The best idea I found is
SELECT ROUND(((DAY(NOW())-1)/7)+1)
select (DATEPART(yyyy , CAST(GETDATE() AS datetime)) * 100 +
DATEPART(ww , CAST(GETDATE() AS datetime))) as week
How will I calculate week number within a date range ? Here my week starts from Saturday to Friday. And I have a start date and end date. With this, how will i calculate using SQL Query ?
Use DATEPART to get the Week number,
and DATEFIRST to set the first day of the week. (See http://msdn.microsoft.com/en-us/library/ms181598.aspx)
Example to get all week numbers in range with Saturday as the first day of week.
SET DATEFIRST 6
SELECT DISTINCT
DATEPART(WEEK, createDate)
FROM
tblUser
WHERE
createDate > '2005-01-01' AND createDate < '2011-01-01'
ORDER BY
DATEPART(WEEK, createDate)
You can use this and your SQL work operates well:
SET LANGUAGE us_english -- with your language
GO
how does one calculate the beginning of a week from a given date e.g 23 March 2010 beginning of the week is 21 March 2010
Depending on the value of DATEFIRST (I'm assuming 7 here, i.e. Sunday):
SELECT columnname - (DATEPART(WEEKDAY, columnname) - 1) AS week_start
FROM Table1
Then week_end is of course 7 days later.