Join tables based on multiple columns

You can do this in Power Query with Table.Join or Table.NestedJoin; as they are, these functions will join on a single column only; you can circumvent this, by replacing the Table parameters with Table.AddColumn, which can add - on the fly - a new, composite column, to join on, something like:

JoinedTable = Table.NestedJoin(Table.AddColumn(Table1, "CompositeColumn1", each [JoinColumn1] & [JoinColumn2]), "CompositeColumn1", Table.AddColumn(Table2, "CompositeColumn2", each [JoinColumn1] & [JoinColumn2]), "CompositeColumn2", "NewCompositeColumn"),

This is new for me, and works perfectly!
Tks

I'm having a similar issue.

I'm trying to merge together the tables so that Ican use two layers in a ArcGIS Map in PowerBI.

Data is broken out per the below:

Table 1: Brand Index

Col1 - Brand

Col2 - Index

Col3 - Latitude

Col4 - Longitude

Table 2: Brand Locations

Col1 - Brand

Col2 - Latitude

Col3 - Longitude

I'd like to merge the datasets so that the result shows:

Col1- Brand

Col2- Type (Index vs Location)

Col3- Index

Col4- Latitude

Col5- Longitude

But when I try to merge the datasets, or append them, I end up with two columns for Latitude and 2 columsn for Longitude. Any advise here would be greatly appreciated.

So, new to Power BI but this is something I'm trying to achieve, using MSProject as input. How can I tell if the tables are "in DirectQuery mode" and how do you "duplicate" columns, is it simply a matter of adding a New Column and setting the formula to “DupCol = Col-I-want-to-join”