Paul Turley continues a discussion on Power BI data model validation:
We often have users of a business intelligence solution tell us that they have found a discrepancy between the numbers in a Power BI report and a report produced by their line-of-business (LOB) system, which they believe to be the correct information.
Using the LOB reports as a data source for Power BI is usually not ideal because at best, we would only reproduce the same results in a different report. We typically connect to raw data sources and transform that detail data, along with other data sources with historical information to analyze trends, comparisons and ratios to produce more insightful reports.
However, if the LOB reports are really the north star for data validation, these can provide an effective means to certify that a BI semantic model and analytic reports are correct and reliable.
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