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
source : cuug
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