【答案】:D 3、若事务 T 对数据对象 A 加上 S 锁,则( )。 T 可以读 A 和修改 A,其它事务只能再对 A 加 S 锁,而不能加 X 锁 T 可以读 A 但不能修改 A,其它事务能对 A 加 S 锁和 X 锁 T 可以读 A 但不能修改 A,其它事务只能再对 A 加 S 锁,而不能加 X 锁 T 可以读 A 和修改 A,其它事务能对 A 加 S 锁和 X 锁 【答案】:C 4、指令( )从主存中读出。
【答案】:B 17、BGP runs over a reliable transport (请作答此空). This eliminates the need to implement explicit update fragmentation, retransmission, acknowledgement, and ( ). Any authentication scheme used by the transport protocol may be used in addition to BGP's own ( )mechanisms. The error notification mechanism used in BGP ( )that the transport protocol supports a “graceful” close, ., that all outstanding data will be delivered ( )the connection is closed.