Splunk does not allow for updating of indexed data. So you are correct that each time there is a change, you will have a new event in Splunk. However, you can still analyze the data correctly by only looking at the latest data by customer. Here is an example:
Sample Data:
custname,mydata,moddate
John Smith,123,07/24/18 09:40:00
Bob Jones,987,07/22/18 12:00:00
Sue Simmons,576,04/12/18 08:00:00
John Smith,321,03/20/17 15:00:00
Bob Jones,142,05/11/16 08:00:00
Search:
index="scratchpad" sourcetype="updateddata"
| stats latest(mydata) by custname
Search Results:
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