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Anonymous's avatar
Anonymous
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4 years ago
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What is the function of Detect Data Changes in Refresh?

Hi  below is my refresh, RangeStart and RangeEnd based on creation-date, Detect Data Changes based on last-change-date   I don't understand the addition of Detect Data Changes. Did some test...
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  • v-easonf-msft's avatar
    v-easonf-msft
    4 years ago

    Hi, Anonymous 

    Please refer to Incremental refresh and real-time data for datasets .

    The Detect data changes setting enables even more selective refresh. You can select a date/time column used to identify and refresh only those days where the data has changed. This assumes such a column exists in the data source, which is typically for auditing purposes. This should not be the same column used to partition the data with the RangeStart and RangeEnd parameters. The maximum value of this column is evaluated for each of the periods in the incremental range. If it hasn't changed since the last refresh, there's no need to refresh the period. In this example, this could potentially further reduce the days incrementally refreshed from 3 to 1.

    Related  tutorial:

    Power BI Incremental Refresh - Understanding Detect Data Changes 

     

    Best Regards,
    Community Support Team _ Eason

Anonymous's avatar
Anonymous
Not applicable
4 years ago

Hi 
I understand, We have a creation datetime, which I use for the incremental refresh RangeStart RangeEnd, and we have a last change datetime, which I use for Detect Data Change. But If you look at my test's, why doesn't it do what I expected?

 

soheil 

parry2k 

v-easonf-msft's avatar
v-easonf-msft
Icon for Community Support rankCommunity Support
4 years ago

Hi, Anonymous 

Please refer to Incremental refresh and real-time data for datasets .

The Detect data changes setting enables even more selective refresh. You can select a date/time column used to identify and refresh only those days where the data has changed. This assumes such a column exists in the data source, which is typically for auditing purposes. This should not be the same column used to partition the data with the RangeStart and RangeEnd parameters. The maximum value of this column is evaluated for each of the periods in the incremental range. If it hasn't changed since the last refresh, there's no need to refresh the period. In this example, this could potentially further reduce the days incrementally refreshed from 3 to 1.

Related  tutorial:

Power BI Incremental Refresh - Understanding Detect Data Changes 

 

Best Regards,
Community Support Team _ Eason