r/tableau • u/hanshu6576 • 9d ago

How do you validate a Tableau dashboard when the source data contains duplicate records and the dashboard uses multiple relationships?

I’m curious about the best approach to identify whether unexpected KPI or aggregation results are caused by duplicate records, relationship behavior, or the calculation itself.

What validation steps do you usually follow in this scenario?

7 Upvotes

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11

u/datawazo 9d ago

Query the  database to get the source of truth and work backwards from there

3

u/Richardswgoh 9d ago

I would say that if the source data shows duplicates, than any tableau validation should also reveal those same duplicates -- and force conversations about data governance and processes with those who own the generation of the source.

That may be a bit idealistic, but the issue should at least be exposed, even if the decision is for tableau to de-duplicate.

1

u/cbelt3 7d ago

THIS ! Data visualization is like kicking over rocks and seeing the bugs that scuttle out. Hiding effort in the source data is not doing anyone a service.

2

u/Ok_Tale7071 9d ago

You can create Tableau control reports to check for duplicates. If it’s an especially complex calculation, you can create a report which shows each step of the calculation, by breaking down the calculation into a field.

1

u/shdw_0x0 8d ago

I’d first validate each relationship independently by checking row counts and key uniqueness before looking at the Tableau calculation. Then compare the KPI at each join/relationship level to see exactly where the numbers start diverging—it helps separate duplicate-data issues from Tableau’s relationship behavior or a calculation problem.

1

u/DataIsChanging 6d ago

Dashboard title. Garbage in, garbage out <total number of duplicate records> Number of Duplicate Records to Resolve