Transform and summarize data from one table into another...

[elietech]

Ok, here is the problem I am faced with.  

I have a data set that records everytime a piece of equipment is removed from service for being unserviceable, and records the time it went "DOWN" (removed) and the time it went back "UP" (returned to service).

What I want to be able to do is determine based on this data overall serviceability rates for all the equipment in a given period of time, and I can't seem to wrap my head around the problem to get what I need.  

I know the total pieces of equipment available, but it might not be consistent on any given day.  (New equipment added, or old equipment removed/obsoleted etc.)

The Up/Down records look like this essentially:

EQUIP_ID, EVENT_ID, DOWN_START (Date/Time field), DOWN_STOP (Date/Time field), DOWN_DURATION (minutes)

The DOWN_DURATION could sometimes span multiple days.  Also, the quipment is expected to be UP more than it's DOWN, and it's certainly not down every day. 

Basically, what I want to do is use this data to create a table like this: 

DATE, EQUIP_ID, SERVICEABLE_TIME

where DATE is a given calendar date covering every date in a date range that could be filtered with a slicer, EQUIP_ID is the unique ID of the piece of equipment, and SERVICEABLE_TIME is the number of minutes the equipment was available and serviceable on that day.

So, I guess my issue here is where to even start with this.  Me and DAX don't get along very well, so I am really up against a wall on this one. 

My other thought, based on everyone's expertise here, is this even something that can be handled with DAX?  Or should I move this transformation further back in my stack and do it serverside in Javascript before it gets sent out over the API to PowerBI? 

[MFelix]

Hi @elietech ,

Looking at your information this is possible however you need to give some additional information on your Model.

I assume you have and equiment table that is related with your down. Create a calendar table disconnected for your filter and the add the following measure:

Measure = 
VAR Date_Selection =
    MAX ( 'calendar'[Date] )
VAR Date_Selection_Next = Date_Selection + 1
VAR temp_table =
    FILTER (
        ADDCOLUMNS (
            Up_Down;
            "Start";
                DATE ( YEAR ( Up_Down[Down_start] ); MONTH ( Up_Down[Down_start] ); DAY ( Up_Down[Down_start] ) );
            "End";
                DATE ( YEAR ( Up_Down[Down_Stop] ); MONTH ( Up_Down[Down_Stop] ); DAY ( Up_Down[Down_Stop] ) )
        );
        [Start] <= Date_Selection
            && [End] >= Date_Selection
    )
VAR DateStart =
    IF (
        MINX ( temp_table; Up_Down[Down_start] ) <= Date_Selection;
        Date_Selection;
        MINX ( temp_table; Up_Down[Down_start] )
    )
VAR DateEnd =
    IF (
        MAXX ( temp_table; Up_Down[Down_Stop] ) >= Date_Selection_Next;
        Date_Selection_Next;
        MAXX ( temp_table; Up_Down[Down_Stop] )
    )
VAR Same_day_selection =
    IF (
        MAXX ( temp_table; [Start] ) = MINX ( temp_table; [End] )
            && MINX ( temp_table; Up_Down[Down_start] ) >= Date_Selection;
        1
    )
RETURN
    IF (
        DateEnd = BLANK ();
        1440;
        IF (
            Same_day_selection = BLANK ();
            DATEDIFF ( Date_Selection; DateStart; MINUTE )
                + DATEDIFF ( DateEnd; Date_Selection_Next; MINUTE );
            1440
                - SUM ( Up_Down[Down_duration] ) * 1440
        )
    )

Check final result in PBIX file attach.

[elietech]

Sorry for the delayed response...this looks very promising....one quick question before I start digging into it....my model already contains a "date/calendar" table...would I need to make another one?  Or can I use the existing one?   And yes, I do have an "Equipment" table that is relatable to the Up/Down events data....

Can't wait to give this a try...definately a level of DAX beyond what I am normally able to dream up on my own 🙂  I'm constantly amazed by the help and support I can find on this community. 

[MFelix]

Hi @elietech,

I use a unrelated table but the use of this other table depends on the relationship you have on your model. 

How does the date table relates with the other tables in the model? 

[elietech]

 Ok, so I implemented your recomended DAX code, and it appears to work, in most situations, but i'm getting some odd results of very large negative numbers, and I can't determine the cause.  I mocked up a report using one month of my data, and I've attached the PBIX file...an ideas on where to start? 

Guess I can't attach files...here is a link to my file in Onedrive

https://1drv.ms/u/s!AswWQQBlp11ZvN1P6rRn-dCyWu7dbw?e=9Hho0X 

[MFelix · Accepted solution]

Hi @elietech .

The error was related with the calculation when you have a single day, I already fixed it by changing the formula to:

measure = 
VAR Date_Selection =
    MAX ( 'Dates'[Date] )
VAR Date_Selection_Next = Date_Selection + 1
VAR temp_table =
    FILTER (
        ADDCOLUMNS (
            UpDown;
            "Start";
                DATE ( YEAR ( UpDown[DOWN_START] ); MONTH ( UpDown[DOWN_START] ); DAY ( UpDown[DOWN_START] ) );
            "End";
                DATE ( YEAR ( UpDown[DOWN_STOP] ); MONTH ( UpDown[DOWN_STOP] ); DAY ( UpDown[DOWN_STOP] ) )
        );
        [Start] <= Date_Selection
            && [End] >= Date_Selection
    )
VAR DateStart =
    IF (
        MINX ( temp_table; UpDown[DOWN_START] ) <= Date_Selection;
        Date_Selection;
        MINX ( temp_table; UpDown[DOWN_START] )
    )
VAR DateEnd =
    IF (
        MAXX ( temp_table; UpDown[DOWN_STOP] ) >= Date_Selection_Next;
        Date_Selection_Next;
        MAXX ( temp_table; UpDown[DOWN_STOP] )
    )
VAR Same_day_selection =
    IF (
        MAXX ( temp_table; [Start] ) = MINX ( temp_table; [End] )
            && MINX ( temp_table; UpDown[DOWN_START] ) >= Date_Selection;
        1
    )
RETURN
    IF (
        DateEnd = BLANK ();
        1440;
        IF (
            Same_day_selection = BLANK ();
            DATEDIFF ( Date_Selection; DateStart; MINUTE )
                + DATEDIFF ( DateEnd; Date_Selection_Next; MINUTE );
            1440
                - CALCULATE (
                    SUM ( UpDown[DOWN_DURATION] );
                    FILTER ( temp_table; UpDown[DOWN_START] = DateStart )
                )
        )
    )

Check result below and attach.

[elietech]

Amazing.  Thank you for your help.  This looks to be exactly the solution to my problem.  I really need to level up my skills with DAX apparently.

[elietech]

Hi @MFelix , maybe if I could trouble you with a small followup to this...

As I started to integrate this into my existing BI report, I noticed a small limitation with this measure...or maybe its a limitation with me....either way, I was wondering:

It seems that this measure works really well, at a super granular level; looking specifically at number of hours available per resource per day.  But it doesn't seem to work if I want to look at something like say, total number of hours available per day for all resources...to try and get an overall sense of the overall serviceability, or by group of resource ( I left out that info from the previous example data I sent, but say each resource belongs to a group, and there are about 5 or 6 different groups total)  

Could this measure be adapted to work for these scenarios as well?  Or would a different measure be required?  

[MFelix]

Hi @elietech ,

As I refered you need to create a different measure based on your context in my case I have made a calculation for the days and ID

Measure 2 = IF(ISINSCOPE(Dates[Date]);[measure]; SUMX(Dates;SUMX(ALLSELECTED(UpDown[RES_ID]);[measure])))

You need to change the two values in SUMX based on the aggregation you need. Be aware that using the disconnected tables and the SUMX can bring some performance issues depending on the size of your data model.

Check PBIX file attach.

[MFelix]

Hi @elietech ,

This measure can be adapter to do a SUMX (aggregator formula) based on the date for example, only question here is that you need to adapt it to each of the categorizations you need, so if it's by day or by machine or by another group.

I will try and give you some pointer tomorrow ok?

[elietech]

Great!  Absolutely no rush at all, I appreciate it!