The following example drops 9 columns from the unpopulated orders table, leaving only 1 column in one column partition.
ALTER TABLE orders DROP o_custkey, DROP o_orderstatus, DROP o_totalprice, DROP o_ordertsz, DROP o_salesperson, DROP o_ordersubstatus, DROP o_ship_addr, DROP o_bill_addr, DROP o_item_count;
Resulting table definition:
CREATE TABLE orders ( o_orderkey INTEGER NOT NULL ) PARTITION BY COLUMN ADD 65531;