Sales details are being stored on a daily basis in the SALES_2007 table. A large amount of data is added to the table daily. To save disk space, you issued the following command: ALTER TABLE sales_2007 COMPRESS FOR ALL OPERATIONS; What would be the outcome of this command?()
A:It produces an error because data already exists in the table.
B:It produces an error because compression can be enabled at table creation only.
C:It compresses all data added or modified henceforth but the existing data in the table is not compressed immediately.
D:It immediately compresses all existing data as well as new data, resulting from either fresh additions or modifications to existing data.
出自:Oracle认证