What is refresh failure vs slow refresh?

< 1 min read

Refresh failure occurs when the dataset fails to update and the new data is not loaded at all.
In one project, a refresh failed due to missing credentials on a source database.
Slow refresh happens when the dataset updates successfully but takes longer than expected.
In another project, a large fact table with complex transformations caused 2-hour refresh times.
Refresh failure breaks SLA and may prevent decision-making.
Slow refresh affects user experience but still delivers data eventually.
Causes of slow refresh include large datasets, broken query folding, and complex DAX or transformations.
Both require monitoring and optimization to maintain reliable BI reporting.

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