Hot Backup

Dear Friends,

From long back, I have doubt on What exactly happening when Database is in HOT BACKUP mode ?

Here we have explaniation for this,

 - When an 'alter tablespace begin backup' command is issued the datafiles that belong to the tablespace are marked as hot-backup-in-progress. 

 - The dirty databuffers in the database buffer cache that belong to the database files are written out to the files and the datafiles are checkpointed. 

 - The datafile headers are updated to the SCN captured when the begin backup is issued. 

 - The datafile headers are not updated until the 'alter tablespace end backup' command is issued;

 - However, the datablock within the database files can continue to be read and updated. 

 - When the datafile is restored from a hot backup, the recovery will begin from the SCN captured during the begin backup is issued. 

 - All changes applied during the hot backup time period will be rolled forward from the redo logs.

Hope this information will clear all our doubts.