有氧耐力训练
MustInherit修饰符用于"抽象类"。
广州公共汽车561路“柯子岭――车陂”，始末站为“柯子岭”和“车陂”，安排两个站长（基层调度员）分别负责这两个始末站的调度组织工作。设该线路17：00~18：00为高峰期，行车作业方案为高峰期单程运行时间40min，平峰期为35min。某天编号为001的车辆在线运行片段如下：第3车次在18：40从“柯子岭”发车开出，发车间距为5分钟，车辆在19：20到达终点站“火车站”，运行是否正点？
Your database operates in ARCHIVELOG mode. User-managed consistent backups are performed every Sunday night. On Tuesday， client A drops a table at 8：00 a.m. as follows： SQL> DROP TABLE cust_ord PURGE； Table dropped. Client B executes a query at 9：00 a.m. on the same table as follows： SQL> SELECT * FROM cust_ord； SELECT * FROM cust_ord *ERROR at line 1：ORA-00942： table or view does not exist Client B needs the dropped table and reports the problem to you.With reference to this scenario， which action should you take？（） retrieve the table by using the flashback feature。 restore all the data files from last Sunday’s backup and then perform a time-based recovery。 restore all the data files from last Sunday’s backup and then perform a log sequence recovery。 restore all the data files from last Sunday’s backup and then perform a cancel-based recovery。 restore from last Sunday’s backup only data files that belong to the tablespace in which the table was stored and then perform a complete recovery。
可以使用GetChildRows方法检索指定主表记录的所有子表相关记录。
Which code， inserted at line 16， correctly retrieves a local instance of a Point object？（）
