checkpoint no. [message #54064] |
Mon, 28 October 2002 03:04 |
shobhit sati
Messages: 2 Registered: October 2002
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Junior Member |
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are checkpoint number(is their anything like checkpoint number) and scn no are updated at the same time in the datafile header when full checkpoint is occuring.
if so what is the difference between the two.
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Re: checkpoint no. [message #54076 is a reply to message #54064] |
Mon, 28 October 2002 11:54 |
Trifon Anguelov
Messages: 514 Registered: June 2002
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Senior Member |
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Every time you commit a transaction the SCN is increasing. These numbers are recorded in the redo logs as well as in the checkpoint record.
The checkpoint record contains the value indicating the point in the redo log such that all database changes prior to this point have been saved in the datafiles. The checkpoint records the highest SCN of all changes to blocks such that all data blocks with changes below that SCN have been written to disk by DBWn.
The bottom line, SCN increases every time you commit, the checkpoint record only when you do checkpoint.
Hope that helps,
clio_usa
OCP - DBA
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