why does the result change on a Table.NestedJoin/JoinKind.Inner regarding which table is 1st or 2nd?

[Anonymous]

Hello,

I do an inner nested join on 2 tables A and B like this :

Table.NestedJoin(A, {"UserName"}, B, {"UserName"}, "B", JoinKind.Inner)

Just for "the fun", I did also 

Table.NestedJoin(B, {"UserName"}, A, {"UserName"}, "A", JoinKind.Inner)

It should return exactly the same thing for me but when I do a Rowcount on both results, there is a small difference, how is it possible ?

[Anonymous]

I have actually noticed that the number that differs is the number of UserName doubloons there are in my table B. But still, why does it give a different result with Inner, wether I place table A or B in the 1st or 2nd place in the method shouldn't change the result I think. Can you explain to me the logic of it please ?

[Poohkrd]

Hi, to get the same result, regardless of the order of the tables in the function argument, you should first expand the attached rows into columns.

[Anonymous]

Thank you for your answe rbut sorry I don't understand. Can you explain the reason and what you actually mean please ?