Generate all possible combinations for Columns(cross join or Cartesian product)

Question

I have a Google SpreadSheets doc with three columns A, B and C.

I need to populate the Column C with all the possible combinations of the values in Columns A and B. Please take a look a the capture to see what I mean.

I found this to be done in Excel, here, but it doesn't work in google spreadsheets.

The formula should be useful even for more columns (e.g.: four instead of two)

Can I do this?

Answer 1

Update 201810

Original formula crashes for a big dataset. I described a way to make cross-join with any size of data here.

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Try formula:

=ArrayFormula(transpose(split(rept(concatenate(A2:A&char(9)),counta(B2:B)),char(9)))
 &" "&transpose(split(concatenate(rept(B2:B&char(9),counta(A2:A))),char(9))))

The result:

car red
train red
car yellow
train yellow
car blue
train blue

You may use it again to add another list:

The formula is in cells C2 and E2,

C2 is:

=ArrayFormula(transpose(split(rept(concatenate(A2:A&char(9)),counta(B2:B)),char(9)))&" "&transpose(split(concatenate(rept(B2:B&char(9),counta(A2:A))),char(9))) )

and E2 is:

=ArrayFormula(transpose(split(rept(concatenate(C2:C&char(9)),counta(D2:D)),char(9)))&" "&transpose(split(concatenate(rept(D2:D&char(9),counta(C2:C))),char(9))) )