I have to work with data retrieved and grouped on a weekly basis (ISO week) and my DB is structured on a daily basis (field: DATE). I need to write down a code which is rolling, so that given the current date, it calculate the week and the retrieve data in the previous 3 weeks, too.
So I write in the WHERE clauses:
TO_DATE(TO_CHAR(DATE, 'YYYYWW')) BETWEEN TO_DATE(TO_CHAR(TO_DATE(running_date, 'YYYYMMDD'), 'YYYYWW'), 'YYYYWW')-3 AND TO_DATE(TO_CHAR(TO_DATE(running_date, 'YYYYMMDD'), 'YYYYWW'), 'YYYYWW')
It doesn't seems to work though.
Any suggestions on how to handle the problem?
Thanks a lot!
You have to subtract 21 days when you want to recive the previous 3 weeks. If you subtract 3 then you recive only the last three days.
You need to use 'IW', not 'WW' as the format mask for ISO week. From the Oracle docs:
IW = Week of year (1-52 or 1-53) based on the ISO standard.
WW = Week of year (1-53) where week 1 starts on the first day of the year and
continues to the seventh day of the year.
Related
I'm fairly new to powerbi.
I want to be able to use a slicer to show the last week not the last 7 days.
I know you can use de relative week, but that shows the dates from Sunday to Monday.
I've also red that it's not possible to change the slicer settings for this.
Is it possible to archiev this in another way?
This is my date table https://imgur.com/a/dCcfBAZ
You can add a column that calculates last weeks' weeknumber and compares it to the weeknumber of the date in your row. Find the weeknumber for the current datetime (NOW), subtract 1, wrap that in an IF and you get a boolean to slice with:
LastWeek = IF((WEEKNUM(NOW(),2) - 1) = YourTableName[Weeknum],true,false)
Works the same as the relative week slicer option, but with the week starting on Monday.
All:
I wonder if there is easy way to group timestamp by order of week, for example:
A month usually has 5 or 4 weeks, once given a timestamp( something like UTC time 1483465353929 which is 1/3/2017 that should be put into 1st week group, say we use the first Monday of a month as the starting of the first week of that month, and if the timestamp is early than the first Monday like 1/1/2017, it should be put into previous month's last week group which is 5th week) How can I quickly identify its week order? Any implementation will be appreciated
Thanks
I have a report that takes sales data from a few tables. I want to add a field that will divide the total sales for the given month by the total number of business days in that same month. Is there a way I can calculate that in an expression? Do I need to create a new table in the database specifically for months and their number of business days? How should I go about this?
Thank you
Intuitively, I would say that you need a simple function and a table.
The table is to host the exceptions like Independence day, labor day, etc.
The function will get two parameters: Month and Year (I'm not providing any sample code since you haven't specified which language you are using).
It will then build a date as yyyy-mm-01 (meaning, first day of the month). If will then loop from 2 to 31 and:
Create a new date by adding the index of the loop to the initial date,
Check if the resulting date is still within the month,
Check if it is a working or not working day (e.g. Sunday),
Check if it is found within the table of exceptions.
If the created date passes all the above tests, you add 1 to the counter.
Though it might look complex, it is not and it will provide you the correct answer regardless of the month (e.g. Feb.) and the year (leap or not).
I want to use Date.WeekOfYear() Function to get Week Number for datetime values, but with a custom day as the start of the week (Let's say Saturday rather than Sunday). How is it possible in PowerQuery M?
You could use a conditional statement like this (adding 1 to the weeknumber if the day is saturday):
if Date.DayOfWeek([Date])=5 then Date.WeekOfYear([Date])+1 else Date.WeekOfYear([Date])
I have a query that needs to return the "week of year" of a date field but the customer of the query uses a non-standard first day of the week so TO_CHAR with 'IW' isn't returning the expected result. In this case the first day of the week is Saturday and Friday is the seventh day of the week.
With T-SQL I'd use DATEPART and SET DATEFIRST.
What is the Oracle equivalent? The Oracle answers I've found in the google all talk about setting the NLS_TERRITORY like so ALTER SESSION SET NLS_TERRITORY = 'UNITED KINGDOM'; but I'm not seeing where I can pick an arbitrary day (other than perhaps finding a territory that uses Saturday).
IW works with a Monday - Sunday week, so this should get you what you are looking for. Basically, get the week according to the day 2 days from now:
to_char(your_date + 2, 'IW')
Oracle's default week format calculates the week number from the first day of the year instead of the first day of the week.
So if a year starts on 01-jan-2009 and the first day is on Wednesday, the week No. 1 will be from 01-jan-2009 to 08-jan-2009 (wednesday to tuesday).
You can use the "iw" format (and a little tweak) if you need the week range to start from sunday through saturday. http://download-uk.oracle.com/docs/cd/B14117_01/server.101/b10749/ch9sql.htm#CIHGFJEI
Try this code below. I basically use the "IW" format and add a condition to get the week number to start from a given date.. say...01-jul-2008.
select target_date,
to_char(target_date+1,'iw') week_sun_thru_saturday,
to_number(to_char(target_date+1,'iw')) -
to_number(to_char( to_date('10-jul-2008','dd-mon-yyyy')+1,'iw')) week_from_01_jul_2008
from t;
Remember..This code will not give week number 1 from jul1st to jul-07 .unless of course 01-jul-2008 is a sunday ;)