How a update statement works internally in oracle

Hi,
I just wanted to know when a user issues a update (any DML) statement, what are all the steps involved?
Like when user updated some statement, the modified block goes to the undo tablespace and new data will be stored in the user PGA and when user issues a commit statement.Does it delinked it from the uno tablespace and lgwr flushed the block to the redo logfile(does the lgwr also flushed the uncommited changes to the logfile as datafile stores the committed as well as uncomitted data).Can anybody suggest me how all the things work internally?

Hi,
Many of the people post across the same questions and lot of discussions carried out. You can you answer straight from Oracle Docs.
Any how refer to the following below links
http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:288016031632
Update Statement-10G
- Pavan kumar N

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How update statement works

Hi all,
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Thanks
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i mean what happens in background in oracle server
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Regards
Amit Raghuvanshi

Update statement works in oracle RAC

Hi Experts,
How the update statement works in oracle RAC environment.
And why we need a separate redo for each instance what will happen if we wont give.
Regrds
Suneel

user1175505 wrote:
Hi Experts,
How the update statement works in oracle RAC environment.UPDATE does not know or care if it on RAC or single instance.
And why we need a separate redo for each instance what will happen if we wont give.you can't start Oracle DB without any REDO.
Handle:     user1175505
Status Level:     Newbie
Registered:     Jun 9, 2010
Total Posts:     610
Total Questions:     249 (182 unresolved)
WOW! Why do you waste your time here when you rarely get answers to your questions?

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Hi,
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Update statement in Internal Table

Plz tell me the syntax and e.g. of update statement in Internal Table program
Moderator message: Welcome to SCN, please research yourself before asking basic questions.
Edited by: Thomas Zloch on Feb 25, 2010 12:47 PM

Hi,
Use UPDATE statement , check below description from SAP help.
UPDATE dbtab FROM TABLE itab. or UPDATE (dbtabname) FROM TABLE itab.
Effect
Mass update of several lines in a database table.Here, the primary key for identifying the lines tobe updated and the values to be changed are taken from the lines of theinternal table itab.
The system field SY-DBCNT contains the number of updated lines,i.e. the number of lines in the internal table itab which havekey values corresponding to lines in the database table.
Regards
L Appana

How to update version of XDK on Oracle 8.1.7.4

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Hi,
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Message was edited by:
Christoph G.

HI ,
Check below links for Mapping,
/people/udo.martens/blog/2006/08/23/comparing-performance-of-mapping-programs
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/people/sravya.talanki2/blog/2005/08/16/message-mapping-simplified--part-i
/people/sravya.talanki2/blog/2005/12/08/message-mapping-simplified-150-part-ii
/people/stefan.grube/blog/2006/01/09/the-use-of-suppress-in-the-xi-30-graphical-mapping-tool
http://help.sap.com/saphelp_nw04/helpdata/en/49/1ebc6111ea2f45a9946c702b685299/frameset.htm
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Update Statement Works Differently on Two Different Systems

I write the code
Data: it_eaus like eaus occurs 0 with header line,
wa_eaus type eaus.
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modify it_eaus from wa_eaus transporting aedat aenam storausz where auszbeleg = '000000000001'.
update eaus from table it_eaus.
endif.
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Hi Prashant,
Thanks for your reply
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Regards,
Kavya

How open cursor statement works

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OPEN CURSOR [WITH HOLD] dbcur FOR
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         [ORDER BY sort_key].
i want to know what does open cursor statement do, how it works, what does dbcur contain?

Hi,
dbcur is cursor name gn by u....
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here in open cursor statement u don hav INTO(destination) right
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close cursor.....................
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Hi all , hoping i can get some help on this one.
We have release a pm workorder and then updated the tasklist.
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This would be similisr to re-exploding a BOM in PP.
Thanks for all your help

There's no standard way of doing this other than deleting the operations and re-importing the relevant task list
PeteA

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Message was edited by: Mc Apple

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How the check statement works in a a loop

Hi gurus,
assume itab has 5 records.
Loop at itab.
ctr = ctr + 1
write: sy-tabix.
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Pls give me the expalanation.

Hi,
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How a update statement works internally in oracle

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