Examine the description of the PRODUCT DETAILs table:
Name Null type
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PRODUCT_ID NOT NULL NUMBER(2)
PRODUCT_NAME NOT NULL VARCHAR2(25)
PRODUCT_PRICE NUMBER(8,2)
EXPIRY_DATE DATE
Which two statements are true?
A.PRODUCT NAME cannot contain duplicate values B.EXPIRY DATE contains the SYSDATE by default if no date is assigned to it C.EXPIRY DATE cannot be used in arithmetic expressions D.PRODUCT PRICE can be used in an arithmetic expression even if it has no value stored in it. E.PRODUCT PRICE contains the value zero by default if no value is assigned to it F.PRODUCT ID can be assigned the PRIMARY KEY constraint正确答案DF
