多项选择题
A.It is possible to have multiple database writers in an Oracle instance.
B.It writes dirty buffers， if any， to data files whenever a checkpoint occurs.
C.It writes dirty buffers， if any， to data files whenever a transaction commits.
D.It writes dirty buffers， if any， to data files before the log writer （LGWR） writes.
单项选择题 View the Exhibit and identify the component marked with a question mark. （）
单项选择题 Notethefunctionalitiesofvariousbackgroundprocesses： 1：Performrecoveryatinstancestartup.SMON 2：Freetheresourcesusedbyauserprocesswhenitfails.PMON 3：Cleanupthedatabasebuffercachewhenaprocessfails.PMON 4：Dynamicallyregisterdatabaseserviceswithlisteners.PMON 5：Monitorsessionsforidlesessiontimeout.PMON 6：Cleanupunusedtemporarysegments.SMON 7：Recordthecheckpointinformationincontrolfile.CKPT Whichoptionhasthecorrectfunctionalitieslistedforabackgroundprocess（）
单项选择题 Notethefollowingfunctionalitiesofvariousbackgroundprocesses： 1：Record thecheckpointinformationindatafileheaders.CKPT 2：Performrecoveryatinstancestartup.SMON 3：Cleanupunusedtemporarysegments.SMON 4：Freetheresourcesusedbyauserprocesswhenitfails. 5：Dynamicallyregisterdatabaseserviceswithlisteners. 6：Monitorsessionsforidlesessiontimeout. Whichoptionhasthecorrectfunctionalitieslistedforabackgroundprocess（）