Re: Thinking out loud about a new RPG web framework

[Thorbjørn Ravn Andersen <thunderaxiom@xxxxxxxxx>]

Joe Pluta skrev  den 09-06-2008 19:30:
> Thorbjørn Ravn Andersen wrote:
>   
> > This turned out to be both an interesting exercise and a learning 
> > experience regarding different .  It is not a problem to store a 
> > scrollable resultset as a session attribute in JSP and navigate back and 
> > forth with a PostgreSQL database on OpenSolaris so that was working nicely.
> >   
> >     
> Hold on though - this means you need a stateful HTTP session, right?  
> That is, you keep the database connection from one request to the next.  
> If you have that and 1000 users, and you all use a connection pool with 
> only 100 entries, then the pool will run out of connections.  It's 
> basically a stateful design.
>   
I did not advocate against stateful designs.  I advocated against having 
statefulness more than one place, and you said that I could not create 
an application which could page the result of an arbitrary SQL command 
without recreating the query every time.  Hence this is what I am 
looking at creating a proof-of-concept for.

Connection pools should grow and shrink as needed.  

> > It then turned out that the PostgreSQL JDBC driver loads the complete 
> > resultset in memory when needing to be able to page back and forth, 
> > which was the whole idea to avoid so that was an unpleasant surprise 
> > having 11 million rows in my testset.  So now I've learned that not all 
> > JDBC-drivers are created equal :)
> >   
> >     
> I expected this.  If the result set is truly disconnected, then you 
> would have to either hold all the data in memory, or else you have to 
> create a new index each time.
>   
Or the database would be smart enough to keep the query active and allow 
the resultset to navigate.    This is currently what I expect the i to 
be able to.

--
 Thorbjørn