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From "TomohitoNakayama" <tomon...@basil.ocn.ne.jp>
Subject Re: [jira] Updated: (DERBY-478) Function to force closing connection (and session)
Date Fri, 29 Jul 2005 13:01:05 GMT
Hello.

> It would be interesting to understand the problem that this enhancement is wrestling
with.
> Nakayama-san, can you shed some more light on your reasons for logging this bug?

As Dan and Rick says, it is not recommended to close physical Connection directly when ConnectionPool
was used.
However ,I think there are cases user reluctantly close physical Connection.

For example, if application close database by itself , that application should ensure to close
physical connection too.
However ,  if connection exists in ConnectionPool, there are no way to ensure to close physical
connection.
(This was problem found in DERBY-273. )

Another example,even if application does not close database,it is not out of imagine that
connection falls into illegal state and 
database administrator wants to kill unhealthy connection .
//This would be incompatible to the charter of derby , "zero administration for end users"
....   :(
If the application server that serve the ConnectionPool supports to kill Connection by administrator,
we can leave it.
But if the application server does not support, it can be emergency exit to force closing
connection using function of dbms.

Best regards.

/*

         Tomohito Nakayama
         tomonaka@basil.ocn.ne.jp
         tomohito@rose.zero.ad.jp
         tmnk@apache.org

         Naka
         http://www5.ocn.ne.jp/~tomohito/TopPage.html

*/
----- Original Message ----- 
From: "Rick Hillegas" <Richard.Hillegas@Sun.COM>
To: "Derby Development" <derby-dev@db.apache.org>
Sent: Friday, July 29, 2005 2:33 AM
Subject: Re: [jira] Updated: (DERBY-478) Function to force closing connection (and session)


>I agree with Dan.
>
> PooledConnection exposes a getConnection() method which returns its wrapped
> Connection object. I suspect the intention is that that Connection is itself a wrapper
whose close()
> method deliberately does not close the underlying physical Connection. Being able to
> close the underlying Connection would work at cross-purposes to the whole idea
> of Connection pooling.
>
> It would be interesting to understand the problem that this enhancement is wrestling
with.
> Nakayama-san, can you shed some more light on your reasons for logging this bug?
>
> Thanks,
> -Rick
>
> Daniel John Debrunner wrote:
>
>>Rick Hillegas wrote:
>>
>>>Hi David,
>>>
>>>Where in the JDBC 4 spec would this be? I seem to have missed it.
>>>There's a fairly long  section on Connection Pooling, but I didn't see
>>>this issue addressed.
>>>
>>
>>I'm not sure it should be. Applications should not have the ability to
>>close the underlying physical connection from their logical connection
>>object. An api exists to close the physical connection, the close method
>>on PooledConnection. But applications do not (and should not) have
>>access to PooledConnection.
>>
>>Dan.
>>
>>
>>
>>
>>
>>>Thanks,
>>>-Rick
>>>
>>>David Van Couvering wrote:
>>>
>>>
>>>>Isn't this part of the proposed interfaces for the JDBC 4 spec?
>>>>
>>>>Tomohito Nakayama (JIRA) wrote:
>>>>
>>>>
>>>>>    [ http://issues.apache.org/jira/browse/DERBY-478?page=all ]
>>>>>
>>>>>Tomohito Nakayama updated DERBY-478:
>>>>>------------------------------------
>>>>>
>>>>>       Summary: Function to force closing connection (and session) (was:
Force to close connection and session)
>>>>>   Description: When connection exists in ConnectionPool , there are
>>>>>no way to ensure closing connection inside the ConnectionPool from
>>>>>application program just using jdbc interface.
>>>>>
>>>>>I think there exists needs to force closing connection when it is
>>>>>needed to ensure closing of connection.  was:When connection exists
>>>>>in ConnectionPool , there are no way to ensure
>>>>>
>>>>>
>>>>>
>>>>>>Function to force closing connection (and session)
>>>>>>--------------------------------------------------
>>>>>>
>>>>>>        Key: DERBY-478
>>>>>>        URL: http://issues.apache.org/jira/browse/DERBY-478
>>>>>>    Project: Derby
>>>>>>       Type: Improvement
>>>>>> Components: Network Server
>>>>>>   Reporter: Tomohito Nakayama
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>When connection exists in ConnectionPool , there are no way to
>>>>>>ensure closing connection inside the ConnectionPool from application
>>>>>>program just using jdbc interface.
>>>>>>I think there exists needs to force closing connection when it is
>>>>>>needed to ensure closing of connection.
>>>>>
>>>>>
>>>>>
>>>
>>>
>>
>>
>>
>
>
>
>
>
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> 



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