I am wondering in a three tier architecture with Weblogic as Application Server and connecting to Oracle 8.1.6 through JDBC, if let's say there are 10 connections in the database which are active querying the database what happens if application server crashes? Will all the connection be terminated or simply once a sesion connects to database it forgets about the connection between Weblogic & Oracle therefore no matter what happens to Application Server the session would stayed connected until the query finishes?
I think all connections would be terminated, correct or I am wrong?
02-06-2001, 05:26 PM
When 10 different app server processes create individual jdbc connections without using a connection pool there would be 10 sessions and not 1. If you are using a connection pool, then there would be the number of sessions specified in the connection pool configuration directives in the weblogic config file.
I have seen mixed results in this kind of an environment. If the application crashes and the developers are catching the exceptions and closing all connections you would be fine. But if the application server crashed, I had seen a lot of hung sessions.
02-06-2001, 05:52 PM
I make a pardon, I forgot to mention that this Weblogic application server has 3 connection pools
Would crash in production enviroment though
Also i find that the way connection pool works is pretty similar to multi threaded server, the only difference I can find is that to return a connection to the connection pool we would have to do it from application, in MTS dispatcher would take care of this isnt it? Are there anymore differences :-?
[Edited by pando on 02-06-2001 at 05:56 PM]
02-06-2001, 07:43 PM
You are correct as far as my knowlege regarding the pool goes. One new solution I am trying currently is to use the connection manager to multiplex connections to an MTS server.
I will let you know once I do some indepth analysis of this setup