List.Max seems to invoke query it refers to

[vincentnoot]

For my use case, I am using 2 tables to make an incremental refresh. One (Query A) has the archive of records, the other (Query B) loads new rows based on a Timestamp field in Query A that it uses as a filter parameter in the API call.

In order for Query B to update the new fields, it needs to read the maximum timestamp value from Query A. I use List.Max to get that value. 

However, instead of fetching the max value of Query A as it is, List.Max in Query B returns the maximum value from the database through Query A. In other words, it seems like Query B invokes Query A to load, then returns the max timestamp from the refreshed Query A.

I want to return the Max Timestamp value from Query A from the data that's already been loaded in the past, without updating Query A.

Is there any way to work around this issue?

Many thanks!

[lbendlin · Accepted solution]

Not really.  You can much about with sequential loading of tables but that will fail too due to the dependencies in the code.

What you really need is to define your max value in an independent call to the data source (rather than looking at table A).

Out of curiosity - once you have loaded table B into Power BI, what is the next step?  Are you also writing the data into the data source?

You might want to consider using incremental refresh instead.

Keep in mind that Power BI  has no memory. You cannot use it for data storage (and expect it to be reliable at that). Your data source stays the original, well, source.