Does backup mode stops writing into datafile?and increase in log file generation relates to this concept.
Explanations pls Thanks.
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Does backup mode stops writing into datafile?and increase in log file generation relates to this concept.
Explanations pls Thanks.
When you place a tablespace in backup mode, the Oracle instance notes that a backup is being performed and internally compensates for it. As you know, it is impossible to make an authentic copy of a database file that is being written to. On receipt of the command to begin the backup, however, Oracle ceases to make direct changes to the database file. It uses a complex combination of rollback segments, buffers, redo logs, and archive logs to store the data until the end backup command is received and the database files are brought back in sync.
Gopu
err not true, the datafile DO get written to, that is so horribly wrong.Quote:
Originally Posted by gopu_g
All that happens is that the datafile headers get frozen.
Stop writing rubbish
got a thread
http://www.speakeasy.org/~jwilton/or...ot-backup.html
but can't find exact thread from metalink and Reason for Increase in redo log generation during bkup can't find exact thread.
what have you smoked...?!Quote:
Originally Posted by gopu_g
And would someone care to explain the dangers of fogetting to take the tablespace out of backup mode after the data file copy has been performed?...
extra redo log generation
believe restarting a database with a tablespace in backup mode will cause problems
It applies all the changes in the block at once to the redologs instead of individual changes when not in backup mode.Quote:
but can't find exact thread from metalink and Reason for Increase in redo log generation during bkup can't find exact thread.
Dave., can u explain me briefly on extra redo log generation.
read below i hope you get it....
http://www.oraclealchemist.com/oracl...ctured-blocks/
Thanks Parag.,
Got a fine explanation with example.