Forum Discussion

captainlaw's avatar
captainlaw
Microsoft Employee
9 years ago

Refresh Data - Append New Data Only

Hello, I'm wondering is it possible to setup refresh of a data source based on date column, meaning only append new data from last load based on date column.  It would be a good feature to add for ...
General Comment
Pankaj1208's avatar
Pankaj1208
Regular Visitor
8 years ago

Hi.... Its good but when i replace the value second time then its not update in previous table so please give the solution 

powerbiuser101's avatar
powerbiuser101
Advocate I
8 years ago

This doesn't work for me either. My dataset does not update on the 2nd refresh. This is rather confusing as I had thought the idea was to append data to "Previousdata" from an ever changing "Dataset"? Based on MarcelBeug's reply, sounds like this was the opposite. I don't understand the "Copy this to PreviousData" step. Shouldn't the Merged/Combined step be added to "Previousdata" rather than "Dataset"?

 

 

 

 

Merged = Table.NestedJoin(PreviousData,{"Date"},NewData,{"Date"},"NewColumn",JoinKind.RightAnti),
    Combined = if Table.IsEmpty(Merged) then PreviousData else Table.Combine({PreviousData, Merged[NewColumn]{0}})
in
    Combined

In my testing, Combined was also referencing an older Table in Merged[NewColumn]. Which made sense to me why it worked the first time and not any subsequent refresh. Re-adding 2 new additional steps as above worked but this would cause some step-bloat if this has to be done every single time I need to append new data.