From: Martijn Tonies
Date: March 11 2005 9:24am
Subject: Re: Better option then polling ?
List-Archive: http://lists.mysql.com/mysql/181150
Message-Id: <019201c5261c$2412f890$3802a8c0@martijnws>
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Hello,

> I am fairly new to mysql and have a strange request .... I am not sure
> if "stored procedures" will solve this.
>
> I have a table in a database that is constantly being updated with new
> information. I would like to be notified if certain information gets
> committed.
>
> Lets say for example the table gets updated every time a login attempt
> happens regardless if it is successful or not.
>
> So I want an app to watch the table for incorrect logins and if found to
> send an e-mail.
>
> Now there are several problems with this ... first... there could be
> hundreds of logins so we do not want the same app to spawn multiple
> processes each notifying the same incorrect login attempt.
>
> I was thinking about a cron that would run every X minute searching any
> newly added rows and keeping the last row id in a tmp file.
>
> Is there a better way ?

Well, as far as I know, not with MySQL. But you might request it
for 5.0 ...

Database engines like InterBase, Firebird and Oracle have
"event mechanisms". Clients can register interest in a particular
event and whenever the database "fires" such an even, the
client will be notified in an asynchronous manner. A trigger on
your table could solve this problem then.

Obviously, this is a much better way compared to polling. :-)

But, as I said, as far as I know, MySQL doesn't support this
(yet).

With regards,

Martijn Tonies
Database Workbench - developer tool for InterBase, Firebird, MySQL & MS SQL
Server
Upscene Productions
http://www.upscene.com