Updated record behavior in data flow incremental refresh

[Narukkp]

Hi Team,

I have a doubt on Power bi Dataflow incremental refresh, If we enable the incremental refresh on dataflow how it will handle the updated records i.e. if suppose I have one employee and his designation has software engineer and after some days he got promoted to senior software engineer, now dataflow will delete the existing record and insert the new record or updated the existing employee record with updated designation ?

Why I have got the doubt  here  we do not have any primary key concept and having only dates filed, so that how dataflow will understand the records is either updated record or inserted record ?

[v-lionel-msft]

Hi @Narukkp ,

The refresh mechanism in Power BI just returns the fact data of the data source or the query results to the dataset in the .pbix file. Whether the data is updated or inserted depends on the data table of the data source.

The refresh strategy is just a mover between the data source and the dataset. This process of moving data is similar to the copy + overlay method.

Best regards,
Lionel Chen

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[Narukkp]

Hi,
@v-lionel-msft  thank you for response but here my ask is internally power bi how it will do  i mean for existing record it will delete and insert the new record or just update the existing record ?

[v-lionel-msft · Accepted solution]

Hi @Narukkp ,

For the existing record, the refresh process will update it, not delete it and add a new record at the end of the table.

Best regards,
Lionel Chen

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[vkarumanchi]

But for me its appending one more record at the end instead of updating the existing record.

scenario : I'm using SQL server and set incremental on abc table ( one month History load and 1 week incremental)

                Updated one record in source before refresh run.

                one record is appended to dataset after refresh don.

Please make it as solution is it seems to be.

Thank you,

Vara

[lbendlin]

Incremental refresh does not handle late updates well. It is designed for data that is immutable after being written.

Until the service supports  full refresh requests of incremental data sources your only remedy at the moment is to initiate a refresh from the desktop which will in turn force a full first refresh of the incremental data source.