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2022年(28)

2021年(8)

我的朋友

分类: Oracle

2022-01-26 16:42:33

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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