Oracle 1Z0-898 問題集

質問 1：
Which two of the following statements are true of embeddable classes? (Choose two)
A. Null comparison operations over embeddable classes are not supported in the Java Persistence query language.
B. An embeddable class must not be used to represent the state of another embeddable class.
C. An embeddable class must not contain a relationship to an entity.
D. An embeddable class can be the key of a Map relationship.
正解：A,D

質問 2：
A developer wants to model the grades for a student as a Map<course, integer>. Assume that Student and Course are entitles, and that grades are modeled by integers.
Which of the following two statements are correct? (Choose two)
A. The mapping for the key of the map can be specified by the @MapKeycolumn annotation.
B. The mapping for the value of the map can be specified by the @Column annotation.
C. The developer can model the grades as an element collection in the Student entity.
D. The developer can model the grades as a oneToMany relationship in the Student entity.
正解：A,C

質問 3：
The developer wants to define a unidirectional relationship from the customer entity to the order entity and map this relationship using a foreign key mapping strategy.
Which one of the pairs of classes below correctly achieves this task?
A. @Entity public class Customer {
@Id int customerId;
@OneToMany (JoinColumn = @joinColumn (name = "CUST_ID") Set <Order> orders;
. . .
}
@Entity public class order {
@Id int orderId;
. . .
}
B. @ Entity public class Customer {
@Id int customerId;
@OneToMany (JoinColumn = @JoinColumn (name = "CUST_ID"), table = ""ORDER) Set
<Order> orders;
. . .
}
@Entity public class order {
@Id int orderId;
. . .
}
C. @Entity public class Customer {
@Id int customerId;
@OneToMany @JoinColumn (name = "CUST_ID") Set <Order> orders;
. . .
}
@Entity public class order {
@Id int orderId;
. . .
}
D. @Entity public class Customer {
@Id int customerId;
@OneToMany Set <Order> orders;
. . .
}
@Entity
@JoinColumn (names = "CUST-ID", referencedColumnName = "customerId")
public class order {
@Id int order Id;
. . .
}
正解：C

質問 4：
An application has two entities, parson and Address.

The application calls the DeletePersonsByStatus named query.
Which of the following is true?
A. The person entities are removed, but NOT their related address entities.
B. The named query will fall.
C. The person entities, and all their related address entities, are removed.
D. The DeletePersonsByStatus named query is ill-formed, and will be rejected by the persistence provider.
正解：C

質問 5：
A developer has created a deep entity class hierarchy with many polymorphic relationships between entitles. Which inheritance strategy, as defined by the inheritanceType enumerated type, will be most performed in this scenario?
A. Joined-subclass (inheritanceType. JOINED)
B. Polymorphic join table (inheritanceType. POLYMORPHIC_JOIN_TABLE)
C. Single table-per-class-hierarchy (InheritanceType.SINGLE_TABLE)
D. Table-per-concrete-class (inheritanceType.TABLE_PER_CLASS)
正解：D

質問 6：
Consider a persistence application with following entity:
@Entity
Public class MyEntity {
@Column (name = "FIELDA_COLUMN")
int fieldA;
int fieldB;
int fieldC;
int fieldD;
An orm.xml is packaged in the application with the following contents:

Which two of following statement are true. (Choose two)
A. fieldD is a persistent attribute of MyEntity
B. fieldB is mapped to column NEW_COLB
C. fieldD is not a persistence attribute of MyEntity
D. fieldA is mapped to column FIELDA
正解：B,C