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Anonymous
Not applicable

Calculating Difference between Two Days based on a variable

Good Day

 

I need assistance with adding a Calulcated Column to my Database.

 

I need worked hours to take the SMR (Hour Meter) from the day it is recorded and subtract it from the SMR of that "same machine" on the shift, and if it is the last shift then the previous day on the first shift. I think I have come right with a formula, but I need to further indicate to it to only subtract once it finds a row with the same EIID as its own.

 

 

GregoryPetzer_0-1657101256456.png

 

1 ACCEPTED SOLUTION

Hi @Anonymous ,

 

You can use VAR to improve preformance.

Previous SMR =
VAR _t =
    TOPN (
        1,
        FILTER (
            DailyProduction,
            DailyProduction[EIID] = EARLIER ( DailyProduction[EIID] )
                && DailyProduction[SMR] < EARLIER ( DailyProduction[SMR] )
        ),
        [Date], DESC
    )
RETURN
    MAXX ( _t, [SMR] )

 

 

Best Regards

Community Support Team _ chenwu zhu

 

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

View solution in original post

5 REPLIES 5
Anonymous
Not applicable

Just to expand, I woudl essentally want the 6911 to rather be the result of the 16298-16294. Then the 2nd line would need to subtract 16294 from the lowest in the shift which would be 16293.

 

Would it be easier to use a function that sorts the data before calculating?

 

GregoryPetzer_0-1657106518692.png

 

Hi @Anonymous ,

 

Don't quite understand your explanation. Can you give simple data and include the expected output values? It is best to share it in a tabular format.

 

Or you can try this expression:

Column =
VAR _last =
    TOPN (
        1,
        FILTER (
            'Table',
            [EIID] = EARLIER ( 'Table'[EIID] )
                && [date&shift] < EARLIER ( 'Table'[date&shift] )
        ),
        [date&shift], DESC
    )
RETURN
    IF ( COUNTROWS ( _last ) > 0, [Shift] - MAXX ( _last, [Shift] ) )

 

Result:

vchenwuzmsft_0-1657509305959.png

Pbix in the end you can refer.

Best Regards

Community Support Team _ chenwu zhu

 

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Anonymous
Not applicable

Hi, that formula doesn't seem to be working, it just generates "-1" in all the columns.
 
I have managed to come up with a formula that works. The only issue is that that data set is over 1m lines, and processing this column takes almost all my memory and 10 minutes to run.
 
Previous SMR =
var _EIID = DailyProduction[EIID]
var _SMR = DailyProduction[SMR]
return
CALCULATE(
MAX(DailyProduction[SMR]),
TOPN(1, FILTER(DailyProduction, DailyProduction[EIID] = _EIID && DailyProduction[SMR]<_SMR), DailyProduction[Date], DESC)
)
 
GregoryPetzer_0-1657520547447.png

 

Hi @Anonymous ,

 

You can use VAR to improve preformance.

Previous SMR =
VAR _t =
    TOPN (
        1,
        FILTER (
            DailyProduction,
            DailyProduction[EIID] = EARLIER ( DailyProduction[EIID] )
                && DailyProduction[SMR] < EARLIER ( DailyProduction[SMR] )
        ),
        [Date], DESC
    )
RETURN
    MAXX ( _t, [SMR] )

 

 

Best Regards

Community Support Team _ chenwu zhu

 

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Anonymous
Not applicable

Thanks a lot! It still takes a while to run but I think that is just the nature of the calculation I am doing. I am changing the actual input of the database to include this number already so that I don't have to calculate it via formula.

 

Thanks again

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