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Shubham_rai955's avatar
Shubham_rai955
Super User
11 months ago
Solved

Error while refreshing dataflow gen2

Facing this issue while refreshing the dataflow, Implemented incremental refresh, and not doing any transformaition using M query in any table. Please guide me how to resolve this.  
  • AntoineW's avatar
    11 months ago

    Hello Shubham_rai955,

     

     Why this happens

    Even though you mentioned no transformations in M, the incremental refresh policy still applies filters and type conversions. If any column expected as Number contains a Text value (or vice versa), Power Query throws this error.


     How to fix it

    1. Check column data types in the source

      • Ensure that the column used for incremental refresh (usually a date or numeric key) and any numeric columns are consistently typed.
      • If the source has mixed types (e.g., numbers stored as text), clean them before refresh.
    2. Add explicit type conversion in Power Query

      • In the Dataflow Gen2 editor, select the problematic column → set Data Type to Text or Number explicitly.
      • Or use try ... otherwise in M to handle invalid values
    3. Validate incremental refresh filters

      • If the policy applies on a column that isn’t strictly numeric or date, adjust it.
    4. Preview the query in the editor

      • Check for rows with unexpected values (e.g., text in numeric columns).

     

    You can also Re-run a full refresh once

    • Disable incremental refresh temporarily.

    • Run a full refresh to confirm if the issue is only with incremental partitions.

    • If full refresh succeeds, re-enable incremental refresh.

     

    Hope it can help you ! 

    Best regards,

    Antoine