Definition
Alsoknownastheoriginalsnapshot,itreferstotherecordingofvariousstatesofinformationatacertainmomentforlaterrecoveryorsubsequentoperations,oftencombinedwithotheroperations.
Application
Mainlyusedinvariousscenarioswheretheinitialdatainformationneedstoberecorded.
First,theinitialsnapshotoftheserver.Recordtherequiredarchitectureanddata,constraints,extendedattributes,indexes,triggers,andsystemtablesfilesatacertainmoment,andtransmittheinitialsnapshottothesubscriberwhenthecopyisperformed.
Second,theinitialsnapshotofthedatabase.Recordthedatabasestatusoftheinformationatacertainmomentinthedatabase,thedataatthattime,andotherinformation,soastofacilitatethelaterrecoveryofthedatabaseandotheroperations.
Three,OSoriginalsnapshot.Recordsystemkerneloperationinformation,usedtoswitchbetweenkernelmodeandusermode.
Four,theoriginalsnapshotofthevirtualmachine.Recordthestateandotherinformationofthevirtualmachine,whichisusedfortherecoveryofthevirtualmachineandsoon.