多项选择题
A. The DGROUP1 disk group was unmounted by another DBA.
B. A datafile has been lost， causing the ASM disk group DGROUP1 to go into the DISMOUNTED state
C. One of the redundant disks （DGROUP1） has been lost in a disk group.
D. This query has no meaning in an ASM instance.
E. A disk associated with a disk group was discovered after the ASM instance initially opened.
单项选择题 You are an Oracle DBA responsible for an ASM instance. The disk controller on your system fails. You suspect that the disk itself is okay. You know it will take 24 hours to replace the controller and you don’t want to have to rebuild the disks from scratch. What do you do？（）
单项选择题 IfyouuseALTERDISKGROUP...ADDDISKandspecifyawildcardforthediscoverystring，whathappenstodisksthatarealreadyapartofthesameoranotherdiskgroup？（）
单项选择题 WhichofthefollowingALTERDISKGROUPcommandsdoesnotuseV$ASM_OPERATIONtorecordthestatusoftheoperation？（）