RE: MUST read Oracle Architecture - Abrief Intro

yes , but time based incomplete recovery could create problems if he doesnt take a full
backup after the os-time-change .

-----Original Message-----
Sent: Wednesday, July 24, 2002 6:39 PM
To: Multiple recipients of list ORACLE-L

Oracle has no concept wrt. the date & time of Operating System for running individually as a product. It just takes the timestamp in certain DML's while updating and inserting the rows having DATE as datatype. Nothing more than this.....

Oracle works on the mechanism of SCN ie. System Change Number which gets monotonically incremented one by one after every commit takes place. It has nothing to do wrt. the OS time.

When the Oracle engine gets started the control file reads the location of datafiles and redo logs and the latest SCN is read and compared with those present in datafiles aand redo logs. If the SCN is not matched menas the database was abnormally shut down and need thread recovery.

Smon does this task independently and roll forwards the txn's which were left in the buffer cache and were not pushed back to d.files during checkpoint process. These txn's were committed at the user end.

Now the ones which were not committed would be rolled back internally by Oracle b'ground process SMON or Server Process initiated by user process and would rollback the blocks who soever touches them first.

A little bit of ARCHITECTURE OF ORACLE .............. Bye for now.

No problems at the time lagging behind or time forwarding of the OS

-----Original Message-----
Sent: Wednesday, July 24, 2002 6:00 PM
To: Multiple recipients of list ORACLE-L

Oracle will continue to work fine (as it uses SCN numbers for consistency and transaction logging rather than dates). However, if you have any apps which use timestamps in the data, then I'd do some more investigation for the ramnifications on the application logic side...

-----Original Message-----
Sent: Wednesday, July 24, 2002 7:13 AM
To: Multiple recipients of list ORACLE-L

If you can take the database down for 1.25 hours. I will hesitate to startup the database with time less then last closing time.

Yechiel Adar
Mehish
----- Original Message -----
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> Sent: Monday, July 22, 2002 8:33 PM

> Hi Guys,
>
> I need to put one hour back for my OS(aix) So How will my database(7.3)
> handle this?? What steps I have to take?? Any light regarding that??
>
> Thanks in advance
> peter.
>
>
>
>
> _________________________________________________________________
> Chat with friends online, try MSN Messenger: http://messenger.msn.com
>
> --
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> --
> Author: Peter R
> INET: niagarap_at_hotmail.com
>
> Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
> San Diego, California -- Public Internet access / Mailing Lists
> --------------------------------------------------------------------
> To REMOVE yourself from this mailing list, send an E-Mail message
> to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
> the message BODY, include a line containing: UNSUB ORACLE-L
> (or the name of mailing list you want to be removed from). You may
> also send the HELP command for other information (like subscribing).

--
Please see the official ORACLE-L FAQ: http://www.orafaq.com
--
Author: Yechiel Adar
  INET: adar76_at_inter.net.il

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).
--
Please see the official ORACLE-L FAQ: http://www.orafaq.com
--
Author: Glenn Travis
  INET: Glenn.Travis_at_sas.com

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).
--
Please see the official ORACLE-L FAQ: http://www.orafaq.com
--
Author: Vikas Khanna
  INET: vkhanna_at_quark.co.in

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Ratnesh Kumar Singh
  INET: ratnesh.singh_at_patni.com

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).