Re: Myth of the database independent applications (Was: Are you using PL/SQL)

On 27 mai, 11:24, zigzag..._at_yahoo.com wrote:
>
> > > > > > > I have worked so many projectsusing[the three-tier]
> > > > > > >architecture and performance has never been an issue.
>
> > > > > > Ifyoudon't mind, and for better mutual understanding, would
> > > > > > it be possible to have a (very rough) idea of some metrics
> > > > > > for one of these systems ?
>
> > > > > > I'm notably thinking of system purpose and :
>
> > > > > > - size of stored data (in your prefered unit)
> > > > > > - size of daily data growth
> > > > > > - number of simultaneous users (peak would be most welcome)
> > > > > > - average and guaranteed response time for user interface operations
> > > > > > - number of transactions over your prefered time period.
> > > > > > (peak would be most welcome)
>
> > > > > Our databasewere up to 100GB large. 95% of our queries were indexed
> > > > > based. Systems are used by up to 100 concurrent users
>
> > > > I forgot to ask which kind of hardwareyouuse for
> > > > such a system, sorry
>
> > > HP UNIX boxesdatabaseserver. Windows boxxes - application server.
> > > Usre interface are web based.
>
> > A few more questions, Zigzag, hopefully the last ones :-)
>
> > - On a given site, there is one database server box and
> > one (more ?) application server box, right ? How much
> > memory and CPUs do they have (for the figures given
> > above) ?
>
> > - Presumably, the unix box runs Oracle. Do you support
> > another database?
>
> > - In the business layer, are (some) selects written "by hand",
> > or doyoualways use an object/relational mapper like Hibernate ?
>
> > - Which platform/framework/language doyouuse ?
>
> > - What was the main rationale behind selecting three-tier ?
> > Is it because it is the standard architecture for web UIs,
> > or are there other reasons ?
>
> Thre etier arcjitecture is "standard" as well as good architecture
> because it separates UI, Buisness Logic and database. UI only
> does UT,database only stores data ad busines slogic does the rest.
>
> UI runs on WIndows Server, Databaseand Business Logic on UNIX
> server. We recommend memorie sof 4GB on Windows Server and same for
> UNIX server.
>
> Our applications only run with Oracle database. As I explained eralier
> our developers are Object-Oriented developers they do not want to use
> PL/SQL for business logic because one cannot reuse any of business
> logic written in C++. UI is in Java. Middleware is CORBA.

Yes, I understand better some of your comments, now. Some of the criticisms here were aimed at systems quite different from yours.

The sql used in the business layer is Oracle specific, right ?

Which network speed do you require ?

• Raoul