Date difference when condition met

[Dunner2020]

Hi there, 

I am calculating the date difference between two columns with a condition that if Date A column has '1/01/1900' then do not take the difference. Here is my code:

Diff_in_days  =

Var retail_notify = MAX('Outages'[Date B])

Var interuption_start = MAX('Outages'[Date A])

Var test_con = FORMAT(retail_notify, "dd/mm/yyyy")

RETURN

CALCULATE( DATEDIFF(retail_notify,interuption_start,DAY), FILTER('Outages and Interruptions',test_con <> FORMAT(DATEVALUE("1/01/1900"),"dd/mm/yyyy"))

)

However, it does take the date difference when the Date A column has "1/01/1900". I used the format function because Date A and Date B column has a date/time format. Could anyone help me where am I making the mistake?

[mahoneypat · Accepted solution]

Please try this expression

Diff_in_days =
VAR retail_notify =
    MAX ( 'Outages'[Date B] )
VAR interuption_start =
    MAX ( 'Outages'[Date A] )
RETURN
    IF (
        YEAR ( retail_notify ) > 1900,
        DATEDIFF ( interuption_start, retail_notify, DAY )
    )

If this works for you, please mark it as the solution.  Kudos are appreciated too.  Please let me know if not.

Regards,

Pat

[amitchandak]

@Dunner2020 , Try like

Diff_in_days =
Var retail_notify = MAX('Outages'[Date B])
Var interuption_start = MAX('Outages'[Date A])
RETURN
CALCULATE( DATEDIFF(retail_notify,interuption_start,DAY), FILTER('Outages and Interruptions',not(isblank(retail_notify)) && retail_notify <> DATE(1900,01,01))
)

[Dunner2020]

@amitchandak ,

I tried that but no luck. Here is the output