053 Question No. 256

256.Sales details is 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 is 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 is enabled at table creation only.
C. It compresses all data added or modified henceforth and the existing data in the table are 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.
Answer: C

You specify table compression with theCOMPRESSclause of theCREATE TABLEstatement. You can enable the compression for a existing table by using the these clauses in anALTER TABLEstatement. in the This case, only the data is inserted or updated after compression are enabled is compressed. Similarly, can disable table compression for a existing compressed table with theALTER TABLE...NOCOMPRESSstatement. In the this case, the all data has already compressed remains compressed, and new data is inserted uncompressed.

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053 Question No. 256