How to export data from one data table to other data table on the first of every month?

[abhirajkakani]

Hello,

I have a forecast table which is linked to an online source

Month	Sales
Dec-16	1
Jan-17	2
Feb-17	3

Here the value under 'Sales' keeps on changing for the same month over the period of time. How do i take a snapshot of this table and save it to another data table on every first of the month so that i can have a comparison with the current value and the value which was predicted then?

[Thiyags]

You can create a reference of the table in Query Editor. 

Open Edit Queries. Right click the table and click on Reference. It will create a new reference table.

Right click the reference table and disable Include in "Report Refresh"

[ImkeF]

I'm afraid, but PowerBI isn't designed to store snapshots of data that change over time. The data in it will always be connected to a source and once you refresh your report, everything will be overwritten. 

In theory, there is one mechanism, that could do the trick (create one new query per load (!) -> disable their load -> append them all together), but apart from it being very clumsy and not practical for many use cases, it actually doesn't work when you perform the append ( http://community.powerbi.com/t5/Desktop/Disabling-quot-Include-in-Report-Refresh-quot-Bug-or-feature... ).

Some workarounds for this scenario:

1) Use an R-query to export the current data into csv (in an append-modus). Therefore you should add a date-column when you import your data, so that the resulting table will always show which data belongs to which date. See here: http://www.thebiccountant.com/2015/12/28/how-to-export-data-from-power-bi-and-power-query/

2) Self-referencing hack: http://www.thebiccountant.com/2016/11/15/incremental-load-powerbi/

You should check the ideas-section if there is an idea for your specific use case which you can vote for!