Oracle Forms achieves this (under its optimistic
locking mode) by:

After selecting the data (for display), when an update
is to occur it re-select's using the rowid for the row
to be update and also checks if the columns are still
the same values as the what it originally selected. 
If not, then a "please re-query" message is sent to
the user.

Under its pessimistic model, it issues a
select-for-update as soon as a user starts to modify a
row on screen

hth
connor


 ---
[EMAIL PROTECTED]
wrote: > 
> 
> 
> Hello fellow DBAs',
> 
> I have a weird question that I was asked. My first
> reaction was to answer:
> "There is no such thing", however I was talked into
> posting this question
> here :-)
> 
> 1. An applicaiton selects certain records (from
> different tables) from a
> database..
> 
> 2. When time comes to update some of these records
> in the datbase
> application needs to know if records that it's about
> to update have been
> modified by some other user.
> 
> 3. Currently this is achieved with via triggers.
> Before performing an
> update application checks if trigger updated a
> certain field in the
> database which serves as an indication that
> records/fields of interest have
> been updated.
> 
> For whatever reasons this solutions was found to be
> not sound by a 3rd
> party "consulting" company which reccommended
> "Oracle native technology"
> to perform this check. This company is now
> unreachable and "management" is
> requesting to change the application to follow this
> "review".
> 
> Management explanation of how it needs to be done is
> based on what ADO
> would do where if you perform an optimistoc lock and
> then later on try to
> update an already updated record it would tell you
> about this upfront., or
> you would be able to check upfront WITHOUT requiring
> the DB.  I am not
> familiar with ADO, that much  so I can not comment
> on it.
> 
> Can somebody tell me if they can think of way to
> achieve this?
> 
> I know it sounds rather weird request -- it is.
> 
> Thanks in advance for any thoughts on this,
> Val Gamerman.
> Oracle DBA
> 
> 
> -- 
> Please see the official ORACLE-L FAQ:
> http://www.orafaq.com
> -- 
> Author: 
>   INET:
>
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=====
Connor McDonald
http://www.oracledba.co.uk (mirrored at 
http://www.oradba.freeserve.co.uk)

"Some days you're the pigeon, some days you're the statue"

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