Google-sheets – How to get an array for a range per a column in Google Sheets

I'm looking for creating a similar formula:

=UNIQUE({A:A;B:B;C:C})

So, I need such kind of a range {A2:A;B2:B;C2:C;...} (each column separated with the semicolon) for several hundred columns.

Seem, it will be a mess if I will try to type it manually.

Can it be done by Google Sheets features?