data buffer pool [message #232195] |
Thu, 19 April 2007 14:57 |
IT Guru
Messages: 59 Registered: January 2007
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I want to under stand oracle internal architecture of oracle.
Here what I understood from Oracle University book + my Oracle faculty.
Plz do correct me where I am wrong.
Eg. Trying to update value of last_name of employees table with update command.
[Undo buffer is part of data buffer pool]
1) Server process read & place data dictionary in data dictionary catch [Share_pool].
2) Server process read & place data bock from employees table to data buffer pool.
3) Server process copy data block from data buffer pool to undo data buffer pool.
4) Server process make changes in data buffer pool.
5) Server process write changes in Redo buffer pool.
6) On commit. LGWR process write Redo buffer pool to redo log file.
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What ever changes are made to data are parallel store in Redo buffer log. Only on commit LGWR process copy same to redo log file.
If one go on making change with out commit at one point of time log buffer will get full & will receive error. This way force to either commit or rollback.
If Rollback is issue then get erase from redo buffer pool.
I feel some thing is wrong in process. So If any one can give me exact flow, I will be really great full for same.
Thank you.
A newbie in Oracle
Student
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Re: data buffer pool [message #232500 is a reply to message #232195] |
Fri, 20 April 2007 14:05 |
IT Guru
Messages: 59 Registered: January 2007
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Thanks for response.
So can any one explain me in detail what is process flow for below given task.
1) Update any recode. & commit.
2) Update any recode. & rollback.
3) Millions of update without commit & rollback.
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