250.You want to schedule a job to rebuild all indexes on the SALES table after the completion of a bulk load operation.The bulk load operation must also be a scheduled job that executes as soon as the first file that contains data arrives on the system.How would you create these jobs?
A. Create both jobs by using events raised by the scheduler
B. Create both jobs by using events raised by the application
C. Create a job to rebuild indexes by using events arised by the application and then create another job to perform bulk load by using events raised by the scheduler
D. Create a job to rebuild indexes by using events arised by the Scheduller and then create another job to perform bulk load by using events raised by the application
Answer: D
答案解析：
参考：http://docs.oracle.com/cd/E11882_01/server.112/e25494/scheduse.htm#ADMIN12361
从以下可知，bulk load是File arrival events raised by a file watcher，rebuild indexes是Events raised by your application，An application can raise an event to be consumed by the Scheduler.
两个都是基于事件的。
事件是由一个应用程序或系统进程发送到另一个应用程序或系统进程的消息，指示已检测到某些操作或事件。一个应用程序或进程以以色列(发送)和一个或多个应用程序或进程消耗(接收)的事件。
调度程序使用两种事件:
应用程序引发的事件
应用程序可以引发调度程序要使用的事件。调度程序通过启动作业来响应事件。例如，当库存跟踪系统注意到库存已低于某个阈值时，它可以引发一个事件，启动库存补货作业。
See "Starting Jobs with Events Raised by Your Application".
由文件监视程序引发的文件到达事件
您可以创建一个文件监视器(Oracle Database 11g Release 2中引入的调度程序对象)来监视系统上文件的到达。然后，您可以配置一个作业，使其在文件监视程序检测到文件的存在时启动。例如，用于连锁商店的数据仓库从商店中的销售点系统上传的每日收入报告加载数据。每次有新的一天结束报告到达时，数据仓库加载作业就开始。
See "Starting a Job When a File Arrives on a System"