DATEDIFF calculation error

[mbs2016]

Trying to calculate number of days between two date fields.

Here is what I have,  

Days Overdue = DATEDIFF(MP_REP_DOCUMENT[RDOC_SCAN_DATE], (MP_REP_POSTING[RPST_CLEARING_DATE]), DAY)

Getting the following error:

A single value for column 'RDOC_SCAN_DATE' in table 'MP_REP_DOCUMENT' cannot be determined. This can happen when a measure formula refers to a column that contains many values without specifying an aggregation such as min, max, count, or sum to get a single result.

[Ch]

Hi,

Your method is mostly right, but it needs a SUM for the column names to get it to work. I was assuming that you were wanting the number days after a deadline to make it 'Overdue'. I added an image to describe my thinking. 

I added an extra part in case the end date is met before the deadline. I also added a "*-1" to this but you could just replace the entire second line of the formula with a 0 or whatever you desire.

This is that calculated measure formula: 

Days Overdue = IF(SUM(Data[Deadline])>SUM(Data[End Date]),
DATEDIFF(SUM(Data[End Date]),SUM(Data[Deadline]),DAY)*-1,   
DATEDIFF(SUM('Data'[Deadline]),SUM('Data'[End Date]),DAY))

If you are trying to just get the days between a start date that is always previous to an end date, it is pretty much what you had before except to add the SUMS. I made a calculated measure for the 'Days from Start to End' with this formula:
Days from Start to End = DATEDIFF(Sum(Data[Start Date]),SUM(Data[End Date]),DAY)

Now if you only want Monday-Friday to count as part of the days then it is a bit more complicated.

Hope this helps!

[Brer_J_Cooper]

Hello,
I'm a bit confused. Why would you sum dates? I'm also not sure why it wont perform the calculation for each row on the data in that row, but insists on summing data.