单选题

Evaluate the CREATE TABLE statement:   CREATE TABLE products   (product_id NUMBER (6)  CONSTRAINT prod_id_pk PRIMARY KEY,  product_name VARCHAR2 (15));   Which statement is true regarding the PROD_ID_PK constraint?()

A It would be created only if a unique index is manually created first.

B It would be created and would use an automatically created unique index.

C It would be created and would use an automatically created nonunique index.

D It would be created and remains in a disabled state because no index is specified in the command.

正确答案

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答案解析