Tape streaming is not happening while performing RMAN tape backup. On investigation, you find that it is not because of the incremental backup or the empty file backup and that RMAN is sending data blocks to the tape drive fast enough.What could be a solution to make tape streaming happen during the backup?（）
A、Configure backup optimization
B、Configure the channel to increase MAXOPENFILES
C、Configure the channel to increase the capacity with the RATE parameter
D、Configure the channel to adjust the tape buffer size with the BLKSIZE option
肠梗阻患者非手术治疗期间最重要的是观察（）
A、生命体征
B、腹痛
C、出入液量
D、肠绞窄迹象
E、排便情况
在笛卡儿坐标系中，当X轴的正向向左，Y轴和正向向上，那么Z轴的正向应向外。
A、对
B、错
简述色彩计划的特性。
（）是正确的E-mail地址。
A、mailto:Webmaster@ceiaeC.org
B、Wmailto:master@ceiaec.org
C、http：//www.ceiaeC.org
D、D.http：//www.ceiaeorg
在执行语句SELECT department_id FROM employees，departments WHERE employees.department_id= departments.department_id；时报错，原因是（）。
A、没有给表employees和表departments加别名
B、没有给列department_id加别名
C、不能用employees.department_id=departments.department_id作为条件
D、SELECT后面的department_id没有指定是哪个表