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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Notification when something changes in the DB
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
---
Val_Gamerman/Victoria_Financial.VICTORIA_FINANCIAL_at_lnn.com
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:
>
Val_Gamerman/Victoria_Financial.VICTORIA_FINANCIAL_at_lnn.com
>
> Fat City Network Services -- (858) 538-5051 FAX:
> (858) 538-5051
> San Diego, California -- Public Internet
> access / Mailing Lists
>
"Some days you're the pigeon, some days you're the statue"
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: =?iso-8859-1?q?Connor=20McDonald?= INET: hamcdc_at_yahoo.co.uk 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).Received on Tue Sep 04 2001 - 15:34:40 CDT
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