Which loop to use (for passing table back to start node + changes in table dimensions)?

Hi all,

I’m trying to do repeated (inner+left joins) of a table with itself. With each iteration the table will grow in the number of columns as well as in the number of rows.

So, I’m looking at a start/end loop node pair where I modify the table within the loop and then have the end loop send the modified table back to the start loop node.

My first thought was to use the recursive loop nodes but they cannot deal with the change in dimensions. Other loops that I’ve tried will collect the modified table but not send the changes back. I searched the loop descriptions but none seem to do what I’m looking for.

Which loop do I need to achieve this?

Example, joining a table with itself via a left+inner join on its first and last columns, respectively:

Iteration 0:

A B

B C

B C D

C

D E

E F

Iteration 1:

A B C

A B C D

B C

B C D E

C

D E F

E F

Iteration 2:

A B C

A B C D E F

B C

B C D E F

C

D E F

E F