String parser question based on oracle grammer

Question

If i have a string like :
update employee
set wtKey = name||pno||id
where id is not null
Then my API should return this when i pass "||"
name||pno||id
I tried doing it using ' ' as dilimiter and check to see if the parsed string has || but that won't work when the above update cmd is written in the following manner:
update employee
set wtKey = name || pno || id
where id is not null
(or)
update employee
set wtKey = name|| ' ' ||id
where id is not null
Is there any API or third party stuff that can perform such operation instead of we parsing it based on some assumptions.
Any help would be appreciated

Answer 1

Matt,
In simple terms, whenever you change some thing, its needed to be logged for the recovery. So when we change Oracle's datablock's data, we are creating one entry. The change has an undo entry also related to it, this would go to the Undo block. Now 'go' means we are updating undo block's current image(whatever it may be) with our current undo image for our transaction, a change hence has to be logged, second redo entry. Transaction table again has to be updated to maintain the entries of the current transaction, some records over there are updated, hence redo.
The basic thing is that Oracle would make sure that we have all the changes, where ever they are done, logged in the log files for the crash. In case we wont have it, we wouldn't be able to perform recovery.
A very simplified explanation :-).
Aman....