How can I embed a copy of a table's column as a table within a new column of the original table?

Question

If I have a table like this:

How can I add an embedded copy of Column2 in place of the Error in Custom? I would want the exact same embedded copy of Column2 in each row of Custom.

I tried using Table.FromColumns({{[Column2]}}) and Table.FromList({[Column2]}) , but they both only embed a one row table with only the current row's value from Column2.

I want the embedded table on each row of Custom to have all of Column2's values, like:

Answer 1

In the each statement [Column2] is a shorter version of _[Column2], where _ is the current row. You need to include the step name if you want the whole column. For example, if the current step is Table, you can use Table.FromColumns({Table[Column2]}) in the each statement to add a one-column table consisting of Column2's values. Note that in this case Table[Column2] returns a list so we only need one pair of curly braces.