BC4J Question: How does AM and Connection Pooling work?

Hello everybody,
we are just trying to understand what exactly happens when a BC4J Application Module is created / when a AM is checked out of the pool with respect to Connection and Application Module Pooling. Especially we would like to understand what ConnectionStartegies, EnvInfoProvider and SessionCookies exactly do and when and how to customize them. Especially we would like to use features like virtual private databases (VPD) and proxy authentication (a feature of the Oracle OCI JDBC driver) with BC4J application modules. We found the HowTo about using JAAS and VPDs with BC4J (http://otn.oracle.com/products/jdev/howtos/bc4j/bc4jvpdjaas.html) but there are still questions, e.g. when is the afterConnect() method of an ApplicationModuleImpl called? During the instanciation of an AM or every time it's check out of the pool?
Any info on this topic would be very welcome!
Regards
Stefan

Hi,
1. Setting jbo.doconnectionpooling=false ,
connection pool still exists.
Is it correct ? When you set this parameter to false, you are saying that Connection Pool is not managed by AM, so you need to specify a JNDI Name in Application Module to use a Pool not managed by AM.
2. There is one situation to set
jbo.doconnectionpooling=true. The article said
"when you have a large number of application
module pools all needing to database connections
from the same underlying application user at the
database level. In this case, the many application
module pools can perhaps economize on the total
overall database sessions by sharing a single,
underlying database connection pool of JDBC
connections, albeit at a loss of efficiency of each
one. This choice would be favored only if total
overall database sessions is of maximum priority. "
Does it mean that if we set it to true when we
have many many AM instances and we cannot afford to
have such number of connection instance in the pool
? It's means that the JDBC connections will be shared avoid new Connection at time.
Normally i use Connection Pool not managed by Application Module.
Bye

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hello
there is a table t that defines parent-child relation:
p | c |
6 | 4 |
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4 | 6 |with this query:
select level l, p, c, connect_by_iscycle cycle, connect_by_root p root_p, connect_by_root c root_c
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create table t (p number, c number);
insert into t values(4,5);
insert into t values(4,6);
insert into t values(5,4);
insert into t values(6,4);

Hi,
As always, start with the Oracle documentation. The SQL language manual
http://docs.oracle.com/cd/B28359_01/server.111/b28286/pseudocolumns001.htm#i1009313
says "The CONNECT_BY_ISCYCLE pseudocolumn returns 1 if the current row has a child which is also its ancestor. Otherwise it returns 0."
In this example, CONNECT_BY_ISCYCLE=1 when the current row (let's call it X) is connected to another row (Y) according to the conditions in the CONNECT BY clause, but the c column of Y has already appeared as c in the path leading to X.
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FROM     t
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(5,4)                                        0
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(5,4) -> (4,6)                               1
(6,4)                                        0
(6,4) -> (4,5)                               1
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I wonder if you're thinking the rows in t as vertices. Don't: you'll understand CONNECT BY queries much better if you think of your rows as edges. Think of the individual c values as vertices.
943276 wrote:
Thanks Solomon. From what you say I understand that connect_by_iscycle value = 1 is inherited at all lower levels.No. Remember what the manual says: CONNECT_BY_ISCYCLE means that a node has a child which has already appeared in the path as its ancestor. That node may have other children that either do not hove children (and therefore can't have children that are their own ancestors), or have children whose children are not their own ancestors.
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INSERT INTO t (p, c) VALUES ( 5, 12);
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(4,6) -> (6,4)                                         1
(4,6) -> (6,4) -> (4,5)                                1
(4,6) -> (6,4) -> (4,5) -> (5,12)                      0
(4,6) -> (6,4) -> (4,5) -> (5,12) -> (12,13)           0
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One reason why I would like to use the connection pool for the RDBMS
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-------- Original Message --------
Subject: Re: rdbms realm and connection pool
Date: Wed, 27 Sep 2000 09:32:47 +0100
From: "Terry" <[email protected]>
Reply-To: "Terry" <[email protected]>
Organization: BEA SYSTEMS Inc
Newsgroups: weblogic.developer.interest.security
References: <[email protected]>
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of
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realm
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The delegate pool acts somewhat similarly to a connection pool, and can
even
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Terry
Nirmala devi <[email protected]> wrote in message
news:[email protected]..
>
I think the rdbms realm uses different connection as it need to be setbefore
the connection pool for Database.Is there any that i can point my rdbmsrealm to use
the connection pool for Database instead
Thanks in advance
Nirmala

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Nirmala devi <[email protected]> wrote in message
news:[email protected]..
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I think the rdbms realm uses different connection as it need to be setbefore
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