Had a little problem recently (10 minuts ago) with key columns.
They ask you for a unique data, but though in one hand “aint nobody d’got time for filling da key column” by themselves, and in the other hand you cannot use a autofill sheet/app formula to do so.
To dodge those annoying restrictions, just opent the column edition menue, chose “auto fill” and enter your RNG formula in the “initial value” field. Your initial value is now the random/formula generated you wanted, the man finaly beat the machine!