Segmentation

[Anonymous]

Hello,

I looking for a solution for the following problem. I need to be able to analyze data for a period based on the first occurence for the customer in the period and its previous activity. I have categorization rule I have to apply. Per exemple if the difference between its first activity in the period and the previous (which is not in the period) is 0 or 1 days, it is category 1. if it is between 2 and 5 days is is category 2. Else it is category 3.

I have a customer and date dimension, a fact table who track customer activity by date. Something like that

Customer id	Date	Value
1	2017-11-30	1
2	2017-11-30	2
1	2017-11-29	3
1	2017-11-28	4
1	2017-11-27	5
1	2017-11-26	6
1	2017-11-22	7
1	2017-11-16	8
1	2017-11-01	9

I use the date from the date dimension like a slicer to select the period I want to analyse.  So according the rule I explained:

if the period is between 2017-11-28 and 2017-11-30, I need  measures telling me there is 1 Cat1 (customer #1), 0 in cat 2 and 1 Cat3 (Customer #2).

if the period is betwwen 2017-11-26 and 2017-11-28., the mesaures Cat 1 = 0, Cat 2 = 1 (Customer #1), Cat 3 = 0,....

I tried to apply SQLBI, Segmentation pattern, but it categorise me a customer in several category. A customer can be in  only  1 category for the period selected.

To compute easily difference, I added a last actity column in the fact table where there is the date of the previous actity for the customer, I don't know if there is a good way to get this date using DAX.

I hope I am clear. 

[v-yuezhe-msft]

@Anonymous，

When the period is between 2017-11-28 and 2017-11-30, the previous date for customer 1 is 2017-11-27, right? If so, please create the following columns in your fact table.

previous date = CALCULATE(FIRSTNONBLANK(Table1[Date],Table1[Date]),FILTER(Table1,Table1[Customer id]=EARLIER(Table1[Customer id])&& Table1[Value]=EARLIER(Table1[Value])+1))

Daysdiff = DATEDIFF(Table1[previous date],Table1[Date],DAY)

Then create the following measures in the fact table.

maxday per customer = MAX(Table1[Daysdiff])

Category = IF([maxday per customer]<>BLANK()&&([maxday per customer]= 0 || [maxday per customer]= 1), "Cat 1",IF([maxday per customer]<>BLANK() && [maxday per customer]>=2 && [maxday per customer]<=5,"Cat 2","Cat 3" ))

Regards,
Lydia

[Anonymous]

Thanks @v-yuezhe-msft

I tried your solution but I ahve error with the first formula : previous date = CALCULATE(FIRSTNONBLANK(Table1[Date],Table1[Date]),FILTER(Table1,Table1[Customer id]=EARLIER(Table1[Customer id])&& Table1[Value]=EARLIER(Table1[Value])+1))

EARLIER/EARLIEST refers to an earlier row context which doesn't exist.

Moreover, I am not sure this will work because the "Value" column can have any value so the Table1[Value]=EARLIER(Table1[Value])+1 will not work.

My other question is, will this  solution work for creating a measure for each category. I need to be able to create something like a KPI for each category and having a measure "Category" won't allow me to di that, right ?

Thanks for your help.

Here is the link to my working version: https://1drv.ms/u/s!Ag5lje3-r6cXwRU7dXN9Bam7gLOG

[v-yuezhe-msft]

@Anonymous,

I am not able to access the file you shared. In your scenario, you can add a index column in Query Editor, then right click your table and choose "New column" to apply the following DAX.


previous date = CALCULATE(FIRSTNONBLANK(Table1[Date],Table1[Date]),FILTER(Table1,Table1[Customer id]=EARLIER(Table1[Customer id])&& Table1[Index]=EARLIER(Table1[Index])+1))

Besides, what KPI would you like to create? Could you please post expected result in table format?

Regards,

Lydia

[Anonymous]

Thank you @v-yuezhe-msft

You should be able to download the file. I have it tested by someone and he was able to dl it and open it.

Else try: https://www.justbeamit.com/aipfv

Even if I add the index, I still have the problem with the earlier in the previous year formula "EARLIER/EARLIEST refers to an earlier row context which doesn't exist. " for both Cutomer Id and Index

Regarding  the  KPI, imagine 3 cards visulization in power BI, each one for a category

10                          20                      15

Cat1                     Cat2                  Cat3

Thanks

[Anonymous · Accepted solution]

I think I finally found the solution by Adjusting Dynamic Segmentation pattern to my case:

Cat = 
CALCULATE ( DISTINCTCOUNT(Customer[Id]),
FILTER ( ADDCOLUMNS ( Customer,"CustomerDiff",
CALCULATE ( FIRSTNONBLANK(TOPN ( 1, VALUES (FactTable[DiffInDays] ), FactTable[DiffInDays] ),1),
CALCULATETABLE ( Customer )
,ALLSELECTED ()
)
),
COUNTROWS (
FILTER (
'Cat', NOT(ISBLANK([CustomerDiff])) &&
[CustomerDiff] >= Cat[MinDiff]
&& [CustomerDiff] <= Cat[MaxDiff]
)
) > 0
)

As I am not able to work with the earlier function I adjusted the formula: 

Previous Date = 
var currentDate = FactTable[Date]
var currentCustomer = FactTable[Id]
VAR val = CALCULATE(MAX('FactTable'[Date]),
FILTER(ALL('FactTable'),
'FactTable'[Date] < currentDate
&& 'FactTable'[Id] = currentCustomer
)
)
return IF(ISBLANK(val),DATEVALUE("2017/01/01"),val)

Is Earlier function better ?

[v-yuezhe-msft]

@Anonymous,

I can only reproduce your error when I create a measure using Earlier function. As my post, please create a calculate column, then apply the Earlier formula. 

In your scenario, as long as you get expected previous date value using new DAX formula, it is OK.

Regards,

Lydia