Assign each of your rows a number and then have Col1 = FLOOR(1 + RAND() * 9) for example - alternatively have a formula column set to your random number statement and then have Col1 = 1 in your filter
Sorry but i’m not clear what you are trying to do RAND will only operate on rows not on columns - if you wanted to show random columns then I think the only way to do that would be to organise your dataset the other way (your rows as columns, etc)