Table.NestedJoin with Table.ExpandTableColumn

[Anonymous]

I've been digging in to the M language, and one of the principles I've learned is that a statement using Table.NestedJoin should usually be followed by a statement using "Table.ExpandTableColumn". I was told this can improve performance, but I am not clear on why that is. If anyone could give me some additional information on this, it would be greatly appreciated.

Thanks.

[Anonymous · Accepted solution]

Merely expanding the tables after the nested join preserves query folding. It's still not as fast as plain old Table.Join.

--Nate

[AT2812]

Very helpful answer. 😄

[Anonymous]

Okay, that helps. Thanks.