Oracle 1Z0-807 問題集

質問 1：
You are consulting with a team that has maintained several legacy database for years. They have reviewed the JPA spec and are wondering if the technology would offer benefits over this current SQL base.
Which statement identifies a risk of adopting JPA?
A. JPA may be able to model every table as a class.
B. JPA's query languagerelies on a container to manage the persistence layer.
C. JPA doesn't provides ACID semantics.
D. JPA could render code that requires extensive SQL tuning to perform well.
E. JPA only works with well-known data models.
正解：D

質問 2：
While analyzing an existing web application, you observe the following issues in the source code:
-Duplicatecontrol code is scattered throughout various view. -Businessand presentationlogicare mixed within these view.
The next phase of the project involves refactoring the existing code to address these two issues.
Which design pattern, if employed in the refactoring exercise, would most directly address the two issues?
A. Composite View
B. Dispatcher view
C. Service to Worker
D. DAO
正解：C
解説: (Topexam メンバーにのみ表示されます)

質問 3：
Which type of application would benefit from using the Singleton pattern?
A. A clustered application that can support 200 concurrent users.
B. An application that requires remote monitoring capabilities
C. An application that interacts with external systems in parallel fashion.
正解：C

質問 4：
A company must honor a service-level agreement (SLA) for its application, which states all database requests must execute within three seconds.
Users complain that some requests take longer than five seconds to complete. You have been contracted to fix the problem.
Which course of action do you recommend?
A. Define a plan for isolating the bottleneck, and define indicators that will measure performance under a test load.
B. Add servers to distribute the load.
C. Upgrade the application server and the operating system.
D. Modify the program to implement multi threading and an event-driven design.
正解：A

質問 5：
The integration team has reported a problem in testing a few deployed MDBs. By design, each MDB listens to one of four named queues. Two producers write messages to each queue. The test issues messages of the same payload type that each producer will send, but varies the number or size of these messages to measure the messaging server's performance.
The team has noticed that the utilization remains at the same high rate any time the test writes messages destined for the third MDB. The message server log does not reveal any failure in sending messages to this MDB. Which anticipation expresses cause for this condition?
A. Leaky Abstraction
B. Hot Potato
C. Golden Hammer
D. Cache less Cow
正解：B

質問 6：
A successful web application is used by over two hundred thousand users. Due to this substantial load, the database is over bridged and fails frequently. All data, included critical user records and temporary session data, is stored in the database. Because of resource constraints, a new database system cannot be installed.
Which change will reduce the load on the database?
A. Refactoring the web application to use DAOs to communicate with the database
B. Creating more entity beans to optimize interaction wild the database
C. Adding more web servers to the web tier to distribute the load and reduce the number of transactions on the database.
D. Refactoring the web application to store temporary session data on the web servers
正解：D