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markive
Advocate II
Advocate II

Date.EndOfWeek() doesn't give me a Date/Time that I can verify e.g. 2011-02-21T23:59:590-08:00

Hi, I'm trying to create a report that is Week based. So it wants to visualise the data by week number mainly.

 

I found this fantastic post to help with the Power Query to get ISO Weeks: http://geekswithblogs.net/darrengosbell/archive/2014/03/23/extending-the-powerquery-date-table-gener...

 

This gives me 'WeekEndingFriday' but the dateType is a 'Date'. I want to get Date Ending Sunday and have the time element as being the last posible micro second. Looking at the documentation Date.EndOfDay() should get me that, but when converted to a DateTime it loses it (if it ever has it): https://msdn.microsoft.com/en-us/library/mt260657.aspx

 

I suppose I can just use the following Monday through Add Days and use that for any Where Date is < EndOfCurrentWeek type calculations (my data range spans multiple years so I cannot simply use WeekNum).

 

Haven't spent quite a lot of time on it, why can't I get Date.EndOfDay to give me the correct time element when converted to DateTime. Here is the Power Query Code with the modified extra line highlighted:

 

let CreateDateTable = (StartDate as date, EndDate as date, optional Culture as nullable text) as table => 
  let 
    DayCount = Duration.Days(Duration.From(EndDate - StartDate)), 
    Source = List.Dates(StartDate,DayCount,#duration(1,0,0,0)), 
    TableFromList = Table.FromList(Source, Splitter.SplitByNothing()),    
    ChangedType = Table.TransformColumnTypes(TableFromList,{{"Column1", type date}}), 
    RenamedColumns = Table.RenameColumns(ChangedType,{{"Column1", "Date"}}), 
    InsertDateTime = Table.AddColumn(RenamedColumns, "DateTime", each DateTime.From([Date])), 
    InsertYear = Table.AddColumn(InsertDateTime , "Year", each Date.Year([Date])), 
    InsertQuarter = Table.AddColumn(InsertYear, "QuarterOfYear", each Date.QuarterOfYear([Date])), 
    InsertMonth = Table.AddColumn(InsertQuarter, "MonthOfYear", each Date.Month([Date])), 
    InsertDay = Table.AddColumn(InsertMonth, "DayOfMonth", each Date.Day([Date])), 
    InsertDayInt = Table.AddColumn(InsertDay, "DateInt", each [Year] * 10000 + [MonthOfYear] * 100 + [DayOfMonth]), 
    InsertMonthName = Table.AddColumn(InsertDayInt, "MonthName", each Date.ToText([Date], "MMMM", Culture), type text), 
    InsertCalendarMonth = Table.AddColumn(InsertMonthName, "MonthInCalendar", each (try(Text.Range([MonthName],0,3)) otherwise [MonthName]) & " " & Number.ToText([Year])), 
    InsertCalendarQtr = Table.AddColumn(InsertCalendarMonth, "QuarterInCalendar", each "Q" & Number.ToText([QuarterOfYear]) & " " & Number.ToText([Year])), 
    InsertDayWeek = Table.AddColumn(InsertCalendarQtr, "DayInWeek", each Date.DayOfWeek([Date],1)+1), 
    InsertDayName = Table.AddColumn(InsertDayWeek, "DayOfWeekName", each Date.ToText([Date], "dddd", Culture), type text), 
    InsertWeekEndingFriday = Table.AddColumn(InsertDayName, "WeekEndingFriday", each Date.EndOfWeek([Date],6), type date),
    InsertWeekEndingSunday = Table.AddColumn(InsertWeekEndingFriday, "WeekEndingSunday", each DateTime.From(Date.EndOfWeek([Date], 1)), type datetime),    
    InsertCurrentThursday = Table.AddColumn(InsertWeekEndingSunday, "CurrentThursday", each Date.AddDays([Date], -Date.DayOfWeek([Date],1) + 3), type date), 
    InsertISOWeekJan4 = Table.AddColumn(InsertCurrentThursday, "ISOWeekJan4", each Date.FromText(Number.ToText(Date.Year([CurrentThursday])) & "-01-04") ,type date), 
    InsertISOWeekYear = Table.AddColumn(InsertISOWeekJan4, "ISOWeekYear", each Date.Year([CurrentThursday])) ,   
    InsertISOWeekFirstMon = Table.AddColumn(InsertISOWeekYear, "ISOWeekFirstMon", each 
        if [CurrentThursday] < [ISOWeekJan4] 
        then Date.AddDays([CurrentThursday],-3) 
        else Date.AddDays([ISOWeekJan4], - Date.DayOfWeek([ISOWeekJan4],1) ) 
      ,type date), 
    InsertISOWeekNum = Table.AddColumn(InsertISOWeekFirstMon, "ISOWeekNum", each Number.RoundUp(((Duration.Days(Duration.From([Date] - [ISOWeekFirstMon]))+1) /7 )), type number), 
    InsertISOWeekID = Table.AddColumn(InsertISOWeekNum, "ISOWeekID", each [ISOWeekYear] * 100 + [ISOWeekNum], type number), 
    InsertISOWeekName = Table.AddColumn(InsertISOWeekID, "ISOWeekName", each Text.From([ISOWeekYear]) & "W" & Text.End( "0" & Text.From(([ISOWeekNum]*10)  + [DayInWeek]),3)), 
    InsertISOWeekNameLong = Table.AddColumn(InsertISOWeekName, "ISOWeekNameLong", each Text.From([ISOWeekYear]) & "-W" & Text.End( "0" & Text.From([ISOWeekNum]),2) & "-" & Text.From([DayInWeek])),

    fnPeriod445a = (weekNum) => let 
      Periods = 
        { 
            {(x)=>x<5,  [P=1,Q=1]}, 
      {(x)=>x<9,  [P=2,Q=1]}, 
      {(x)=>x<14, [P=3,Q=1]}, 
      {(x)=>x<18, [P=4,Q=1]}, 
      {(x)=>x<22, [P=5,Q=2]}, 
      {(x)=>x<27, [P=6,Q=2]}, 
      {(x)=>x<31, [P=7,Q=3]}, 
      {(x)=>x<35, [P=8,Q=3]}, 
      {(x)=>x<40, [P=9,Q=3]}, 
            {(x)=>x<44, [P=10,Q=4]}, 
            {(x)=>x<48, [P=11,Q=4]}, 
            {(x)=>true, [P=12,Q=4]} 
        }, 
      Result = List.First(List.Select(Periods, each _{0}(weekNum))){1} 
    in 
      Result,

    InsertPeriod445 = Table.AddColumn(InsertISOWeekNameLong, "Period445Record", each fnPeriod445a([ISOWeekNum])), 
    ExpandPeriod445 = Table.ExpandRecordColumn(InsertPeriod445, "Period445Record", {"P","Q" }, {"Period445", "Quarter445"}), 
    RemovedColumns = Table.RemoveColumns(ExpandPeriod445,{"CurrentThursday", "ISOWeekFirstMon"}) 
  in 
    RemovedColumns
in
    CreateDateTable
InsertWeekEndingSunday = Table.AddColumn(InsertWeekEndingFriday, "WeekEndingSunday", each DateTime.From(Date.EndOfWeek([Date], 1)), type datetime),    
    

Thanks for any help!

 

 

 

3 REPLIES 3
MattAllington
Community Champion
Community Champion

Maybe I have missed something, but if you want a weekly report, why not aggregate your data table on load into weeks, and then just create a week calendar table?  The report will be much more performant. 



* Matt is an 8 times Microsoft MVP (Power BI) and author of the Power BI Book Supercharge Power BI.
I will not give you bad advice, even if you unknowingly ask for it.

Hi @MattAllington, this is exactly what I'm trying to do.. I have the data come in from the API and then I aggregate it in another table based on the week.

 

The problem is my dataset now has over a years worth of data so WeekNum() repeats the first few weeks of 2016. To get around this rather than simply using WeekNum I am using from > to date ranges so that I can keep things seperate over multiple years.

 

Any advise on this would be helpful.. 

 

 

where is your data actually stored?  if it is in a DB, can you (or someone else) write a query that consolidates the data during load - not after load?



* Matt is an 8 times Microsoft MVP (Power BI) and author of the Power BI Book Supercharge Power BI.
I will not give you bad advice, even if you unknowingly ask for it.

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