Hi @Soham_Potdar,
thanks for reaching out!
In the following, I will explain you one way to solve this problem. We will create the following OLAP Table:
image785257 6.32 KB

1. 
   _CASE_KEY: Add the case key as a dimension:

_CEL_P2P_ACTIVITIES_EN."_CASE_KEY"

1. 
   condition: As a first KPI, we want to add the flagging or not flagging condition. This is the hard part of the problem. In the case below, I have chosen the activity Change Quantity to be your Activity A. You can simply substitute the PQL code with your desired Activity A.

*CASE WHEN *
MATCH_PROCESS(NODE[Change Quantity] as src,NODE[Change Quantity] as trg CONNECTED BY EVENTUALLY [ src, trg ]) = 1
AND
MATCH_PROCESS(NODE[Change Quantity] as src,NODE[Change Quantity] as trg CONNECTED BY DIRECT [ src, trg ]) = 0
*AND *
CALC_REWORK("_CEL_P2P_ACTIVITIES_EN".ACTIVITY_EN = Change Quantity) >= 2
THEN flag
*ELSE no flag *
END
explanation of this KPI:
We want to flag a row in the OLAP table if the Activity A is followed by another instance of the Activity A (in the process flow of one CASE ID), BUT Activity A is not directly followed by another instance of Activity A (which means that we have at least one other activity like B,C,D,E in between them), AND there are at least two instances of the Activity A for one CASE ID. If this is correct, then we apply a FLAG, if not then we apply NO FLAG.

1. 
   Activity: Next, we want to add a KPI simply in form of an activity. This is the third column in our OLAP table:

_CEL_P2P_ACTIVITIES_EN.ACTIVITY_EN

1. 
   lagged activity: Last, we add the respective successor activity to every activity displayed in the third column. Simply add a KPI stating:

ACTIVITY_LEAD ( _CEL_P2P_ACTIVITIES_EN.ACTIVITY_EN )
The table is done. We can now filter on specific CASE IDs that are flagged.

Extras:
We can also add conditional formatting. Lets stick to the example above. Our target Activity A is still Change Quantity. In the OLAP settings, we can choose to mark all Change Quantity activities in the third column e.g. yellow background.
If we now filter on a specific CASE ID, we see that the fifth and seventh (last) activity in the process flow of this CASE ID was the Activity Change Quantity:
image811356 21.6 KB
Last, we can add a process explorer to the analysis sheet to have a visually perfect overview of the process flow of the case:
image654550 23.5 KB
From this we can easily see that the Quantity was changed once, then the invoice was booked and then the quantity was changed again.

I hope this procedure solves your problem!
Best,
Your Celonis Team

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