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anongard
Helper I
Helper I

DATEDIFF with blank dates

Hello all,

 

I'm struggling hard with the datediff function right now. My problem is this:

 

I have two columns of dates, column A is a start date and column B is a finish date. Every column has a start date, but not every column has a finish date. I am trying to create a column C that has the age of the record. Using DATEDIFF=(column A, column B, DAY) will return the age in days of the columns with an end date, but since there are null values for those still ongoing, it returns nothing for them. I still need that age! Any thoughts on how to accomplish this?  

 

Thanks,

Alex

 

 

1 ACCEPTED SOLUTION
Anonymous
Not applicable

@anongard,

What days do you want to return for those blank end dates? If you want to return the days between start date and today when the end date us blank, you can use the following DAX to calculate age of the record.

Column = IF(ISBLANK(Table[End Date]),DATEDIFF(Table[Start Date],TODAY(),DAY),DATEDIFF(Table[Start Date],Table[End Date],DAY))
1.PNG


Regards,

View solution in original post

5 REPLIES 5
Anonymous
Not applicable

@anongard,

What days do you want to return for those blank end dates? If you want to return the days between start date and today when the end date us blank, you can use the following DAX to calculate age of the record.

Column = IF(ISBLANK(Table[End Date]),DATEDIFF(Table[Start Date],TODAY(),DAY),DATEDIFF(Table[Start Date],Table[End Date],DAY))
1.PNG


Regards,

hello - instead of using TODAY is there a way to calculate it from date slicer.

user2021_0-1637278970258.png

Column = IF(ISBLANK(Table[End Date]),DATEDIFF(Table[Start Date],TODAY(),DAY),DATEDIFF(Table[Start Date],Table[End Date],DAY))

 

Thank you.

 

 

 

Thank you! Related, but more difficult question:

 

In PowerQuery, I'm trying to replicate this DAX function: TestCourse = IF(Courses[CompletedDate] > Courses[ActivationDate],TRUE,FALSE)

 

However, nothing I've tried in M has worked. I tried first with

 

= if Courses[CompletedDate] > Courses[ActivationDate]

then "TRUE"

else "FALSE" 

 

but I get errors about cyclic references and nothing very helpful to resolve it. If I could sort / filter in the DAX view that would be even better, but I suppose that's the entire point... 

 

Thanks,

Alex

Anonymous
Not applicable

@anongard,

I am not able to reproduce your issue. In Query Editor, add a custom column as shown in the following screenshot.
1.PNG2.PNG

Regards,

I was able to solve this with conditional columns, thankfully. I don't know why it worked for you though, I have literally the exact same thing typed in mine and I still get cyclic errors. Is there something that could be giving it trouble in the data? 

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