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julsr's avatar
julsr
Continued Contributor
7 months ago
Solved

Update semantic model or Dataflow efficiently

Hi everyone!   I need for Power BI to detect which rows have been modified (based on a key such as DateTime, ClientID, etc.) and update them accordingly once the dataflows are refreshed daily (via ...
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  • cengizhanarslan's avatar
    cengizhanarslan
    7 months ago

    Power BI incremental refresh is partition-based, so it can refresh partitions efficiently, but it does not “update individual rows” inside an already-loaded partition.

    Use:

    • RangeStart/RangeEnd on a DateTime column (must fold) 

    • optionally Detect data changes using a separate “LastModifiedDateTime” column so only affected partitions refresh

    But remember, updates are handled by refreshing the whole partition, not row-by-row upserts.

     

    The duplicate value problem probaly happens because of Range Start/End parameters wrong usage. Example filtering should be like below:

     

    = Table.SelectRows(
    Source,
    each [LastModifiedDateTime] >= RangeStart
     and [LastModifiedDateTime] <  RangeEnd
)
cengizhanarslan's avatar
cengizhanarslan
Super User
7 months ago

Power BI incremental refresh is partition-based, so it can refresh partitions efficiently, but it does not “update individual rows” inside an already-loaded partition.

Use:

  • RangeStart/RangeEnd on a DateTime column (must fold) 

  • optionally Detect data changes using a separate “LastModifiedDateTime” column so only affected partitions refresh

But remember, updates are handled by refreshing the whole partition, not row-by-row upserts.

 

The duplicate value problem probaly happens because of Range Start/End parameters wrong usage. Example filtering should be like below:

 

= Table.SelectRows(
    Source,
    each [LastModifiedDateTime] >= RangeStart
     and [LastModifiedDateTime] <  RangeEnd
)