21、Choose three Examine this description of the PRODUCTS table: Name NULL? TYPE ------------------------------------------------------------------------ PROD_ID NOT NULL VARCHAR2(6) QUANTITY NUMBER(8,2) PRICE NUMBER(10.2) EXPIRY_DATE DATE Rows exist in this table with data in all the columns. You put the PRODUCTS table in read-only mode. Which three commands execute successfully on PRODUCTS? A) ALTER TAELE products DROP COLUMN expiry_date; B) CREATE INDEX price_idx on products (price); C) ALTER TABLE products SET UNUSED(expiry_date); D) TRUNCATE TABLE products; E) ALTER TABLE products DROP UNUSED COLUMNS F) DROP TABLE products
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