为什么结构素描舍弃光影变化的刻画，而刻意强调物象本质的结构特征呢？
下面答案中属于流的基本操作的是（）和（）。 读取（Read）。 定位（Seek）。 打开（Open）。 关闭（Close）。
Two data files have been deleted at the operating system level by accident. Your database is running in ARCHIVELOG mode and online backups are taken nightly. One of the data files that has been deleted belongs to the USERS tablespace on the other belongs to the SYSTEM tablespace. How can you recover from this situation？（） Shut down the database, restore the two data files and then start up the database. 。 Take the system and users tablespace offline, restore the two data files, recover the two datafiles, and then bring the SYSTEM and USERS tablespaces online. 。 Shut down the database, restore the two data files, start up the database in MOUNT mode, recover the two data files, and then alter the database open. 。 Take the SYSTEM and USERS tablespaces offline, recover the two datafiles and then bring the SYSTEM and USERS tablespaces online.。
着火必须有三要素，一是可燃料，二是火种，三是（） 氧气。 乙炔。 氢气。 二氧化碳。
When the AIM-CUE is being used, where do log messages go if the log file is full?（） The initial log file is named message.log.prev, and a new file named message.log is started. 。 Once the log file is full, the oldest log entries are dropped to make space for new entries. 。 When the log file becomes full, it is automatically copied to an external server and a new message.log file is started. 。 Once the log file becomes full, it stops logging new messages and the new log messages are lost.。
曹禺一生共写下了剧本（）。
