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manoj_0911's avatar
manoj_0911
Icon for Kudo Commander rankKudo Commander
2 months ago
Solved

Does Power BI Process Refresh Partitions Sequentially or in Parallel?

Hi Team,

 

I would like to understand the expected Power BI refresh behavior from a SQL Server perspective.

During both Incremental Refresh and Full Refresh operations, our DBA observed multiple SQL queries running simultaneously against the source database.

For example, during Incremental Refresh, queries for multiple date ranges/partitions appear to run at the same time:

DATE_TIME >= '2026-06-11' AND DATE_TIME < '2026-06-12'
DATE_TIME >= '2026-06-12' AND DATE_TIME < '2026-06-13'
DATE_TIME >= '2026-06-13' AND DATE_TIME < '2026-06-14'
DATE_TIME >= '2026-06-14' AND DATE_TIME < '2026-06-15'

Could you please confirm:

  1. During Incremental Refresh, does Power BI process partitions sequentially or can multiple partitions be processed in parallel?

  2. During a Full Refresh, does Power BI process tables/partitions sequentially or can multiple queries run concurrently against the source database?

  3. Is there any Microsoft documentation that describes this behavior?

  4. Is there any Power BI setting that controls or limits refresh parallelism?

We are trying to understand whether seeing multiple concurrent SQL queries during a Power BI refresh is expected behavior or not.

Thanks.

Need Help
  • Rupa01's avatar
    Rupa01
    2 months ago

    Hi manoj_0911,

     

    Incremental Refresh - 
    Power BI creates multiple partitions and processes them during refresh. These partitions are not processed strictly one after another, multiple partitions can be processed in parallel (subject to engine limits and capacity).
    Microsoft explains the partitioning behavior here - https://learn.microsoft.com/power-bi/connect-data/incremental-refresh-overview 

     

    Full Refresh - 
    Similarly, during a full refresh, Power BI does not process all tables or partitions sequentially. Multiple tables and/or partitions can be refreshed concurrently, which means multiple queries can hit the SQL Server source at the same time.

     

    Control over Refresh parallelism - 
    There’s no direct setting to control partition-level parallelism in Power BI. However, with Premium/PPU and the XMLA endpoint, you can explicitly control how partitions are processed.

    Microsoft explains Advanced incremental refresh and real-time data with the XMLA endpoint - https://learn.microsoft.com/power-bi/connect-data/incremental-refresh-xmla 

     

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    Best regards,
    Rupasree Achari | BI & Fabric Analytics Engineer 

5 Replies

  • Rupa01's avatar
    Rupa01
    Icon for Solution Sage rankSolution Sage
    2 months ago

    Hi manoj_0911,

     

    Incremental Refresh - 
    Power BI creates multiple partitions and processes them during refresh. These partitions are not processed strictly one after another, multiple partitions can be processed in parallel (subject to engine limits and capacity).
    Microsoft explains the partitioning behavior here - https://learn.microsoft.com/power-bi/connect-data/incremental-refresh-overview 

     

    Full Refresh - 
    Similarly, during a full refresh, Power BI does not process all tables or partitions sequentially. Multiple tables and/or partitions can be refreshed concurrently, which means multiple queries can hit the SQL Server source at the same time.

     

    Control over Refresh parallelism - 
    There’s no direct setting to control partition-level parallelism in Power BI. However, with Premium/PPU and the XMLA endpoint, you can explicitly control how partitions are processed.

    Microsoft explains Advanced incremental refresh and real-time data with the XMLA endpoint - https://learn.microsoft.com/power-bi/connect-data/incremental-refresh-xmla 

     

    💡 Helpful? Give a Kudos 👍 — keep the community growing
    ✅ Solved your issue? Mark as Solution ✔️ — help others find it faster

    Best regards,
    Rupasree Achari | BI & Fabric Analytics Engineer 
  • Parchitect's avatar
    Parchitect
    Icon for Solution Sage rankSolution Sage
    2 months ago
    Just to add a bit more context from the engine perspective, and not add same information as other correct replies in the post.

     

    The behavior you’re seeing (multiple SQL queries running at the same time) is expected and comes from how the Tabular engine processes data.

     

    Each partition (in incremental refresh) is processed independently, and the engine can process partitions in parallel to maximize throughput. That’s why you see multiple date-range queries executing concurrently against the source.

     

    The same applies to full refresh:
    - multiple tables and partitions can be processed in parallel
    - Power BI uses a limited number of processing slots (typically around 6 concurrent operations by default), so some queries run simultaneously while others queue

     

    Microsoft documentation confirms that partitions in tabular models can be processed either sequentially or in parallel depending on available resources:
    https://learn.microsoft.com/en-us/analysis-services/tabular-models/partitions-ssas-tabular

     

    So from a SQL Server / DBA perspective, seeing concurrent queries during refresh is completely normal and by design.

     

    Best regards,

    Solutions Architect - Microsoft Fabric Specialist - Parchitect

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  • krishnakanth240's avatar
    krishnakanth240
    Icon for Super User rankSuper User
    2 months ago

    Hi manoj_0911 

     

    Incremental Refresh = Power BI processes multiple partitions in parallel and might not be strictly sequential.  

     

    Full Refresh = Tables and partitions can also be refreshed concurrently and multiple queries against SQL Server are expected.  

     

    Documentation Links

    https://learn.microsoft.com/en-us/power-bi/connect-data/incremental-refresh-xmla

    https://learn.microsoft.com/en-us/power-bi/connect-data/incremental-refresh-overview?utm_source=copilot.com

     

    Settings = No simple toggle in Power BI Desktop/Service. Parallelism is managed automatically by the engine and Premium capacity offers more control via XMLA.  

     

    Expected behavior = Yes, seeing multiple concurrent SQL queries during refresh is

    normal. 

  • v-csrikanth's avatar
    v-csrikanth
    Icon for Community Support rankCommunity Support
    2 months ago

    Hi manoj_0911 
    We would like to inquire whether have you got the chance to check the solutions provided by other users in commiunity to resolve the issue. We hope the information provided helps to clear the query. Should you have any further queries, kindly feel free to contact the Microsoft Fabric community.

    Thanks.