You have a durable subscriber, and the subscriber is down or not reachable when the message is produced. Which two options regarding the expiry of these messages are true?（） 正确。 错误。
庭荫树的选择标准 正确。 错误。
One of the users in the PROD database，Adams，complains that his update on the table，TRANS， is taking an unusually long time to complete. You find that the table gets locked by another database user before Adams starts his transactions，and you are unable to contact the user holding the table lock. As Adams is updating some crucial rows in the table， he should get the highest priority. Which method would you use to overcome this problem？（） 正确。 错误。
You have 100 segments in the USERS tablespace. You realize that the USERS tablespace is running low on space. You can use Segment Advisor to （） 正确。 错误。
下列属于英国1984年《数据保护法》规定了对数据用户“不透露”条件豁免的情况是（） 正确。 错误。
往复式压缩机的活塞环在安装时，注意同组相邻活塞环周向开口应对齐。
