DATEDIFF function that counts first day

[Samoe]

Hello all!

I am building a report and am calculating lead times. My data is structured pretty much like this:

Now, I already had achieved thanks to some help here to create a measure to calucate the days from start to release, for info 

Measure = DATEDIFF(max(Table[Start date]), max(Table[release date]), DAY).

But now I have a problem:

1. In fact, I want to count all the days from start to release because the start day counts already! (so in the first row, this would return 4). However, the datediff function does not count the first day (thus returning 3 in this example).

--> How can I fix this? 

[Greg_Deckler]

@Samoe 

Measure = DATEDIFF(max(Table[Start date]), max(Table[release date]), DAY) + 1

?

[Samoe]

haha, I thought of that too. But then I felt like "this cannot be a good solution". It feels not correct to me to do it like that, even though ofc. the result will be correct 😅

[Greg_Deckler]

@Samoe Lol! Well, you could use COUNTROWS combined with CALENDAR like this:

COUNTROWS(CALENDAR(MAX('Table'[Start date]), MAX('Table'[Release date])))

However, that's probably going to perform significantly less fast. In fact, if you want your function to be as fast as possible, probably should do this:

Measure =
  VAR __Start = MAX('Table'[Start date])
  VAR __End = MAX('Table'[Release date])
  VAR __Result = __End - __Start + 1
RETUR
  __Result