Appending current and historical data

[Anonymous]

Hi all,

I have two datasets seperately where one contains the historical data and other contains only the latest 30days data.I want to append both the datasets in such a way that only the missing dates from the historical data gets picked from 30days data and gets appended to the historical data.For e.g., historical dataset contains data from 1-Jan-2019 to 14-Feb-2021 and the latest 30days dataset contains 21-jan-2021 to 21-Feb-2021 the expected final dataset should contain data from 1-Jan-2019 to 21-Feb-2021.

Thanks in advance,

[V-pazhen-msft]

@Anonymous 

Do you mean 2 tables 1 with current data and 1 with historical data? If so, you can just append them in query editor. 

Paul Zheng _ Community Support Team

[Payeras_BI]

Hi @Anonymous ,

Is this a one-off? If so, in DAX you could make use of EXCEPT and UNION functions.

MISSING DATES = EXCEPT(LATEST30DAYS,HISTORICAL)
and then
UNION(HISTORICAL,MISSINGDATES)

[amitchandak]

@Anonymous , refer if this dax append method can help

https://blog.crossjoin.co.uk/2020/04/13/keep-the-existing-data-in-your-power-bi-dataset-and-add-new-data-to-it-using-incremental-refresh/
https://www.thebiccountant.com/2017/01/11/incremental-load-in-powerbi-using-dax-union/