Servlets and multiple JDBC connections...

Hi Guru's
I want to perform multiple JDBC queries simultaneously from my servlet. Let's say I have a connection pool containing JDBC connections. Now what I want to do is to use each of this connections simultaneously to perform queries in parallel.
What is the best way to do this??? create multiple threads, one for each query, and then collate results when all threads are finished???
Has anyone does this before or know of any links or samples which I can look at??
your help much appreciated...
Many Thanks

Thanks but further questions....
But take care:
multithreading might only work parallel if there are
multiple processors - otherwise the thread fragments
will be processed one after the other until they are
finished.I agree. My server has multiple processors hence multi-threading.
Why do you need to perform the queries
simultaneously?
wouldn't it work too when you perform the queries one
after the other?To speed up performance. Sequential processing is too slow at the moment.
Hope you don't try doing so inside one single
database...yes inside a single databse.
Do you have any links to sample example etc..??? Importantly are you aware of any issues when one does this type of multi-threading from servlet. i.e does it clash with servlet's threading model etc...
I am aware of how servlets multithread requests and am quite familiar with them. Just wanted some examples on multithreading JDBC connections from servlets and how I can wait for all threads to finish before collecting results....also wanted to make sure that there are no other issues....
further help will be much appreciated.....

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Hi
I have WLI application ( 7.0 ) and another J2EE appliction configured on WLS (
7.0 ). If I have multiple jdbc connection pools configured to access different
( or even the same ) databases, I am unable to get the connection to execute a
sql query in the J2EE app. The connection pool gets initialized properly during
the server startup and I can see them in the console but when I try to acquire
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and WLI and another J2EE app to run together on WLS 7.0? Any suggestions are welcome.
Thanks
Sreeram

Well ... It boiled down to ACLs.
"Sreeram" <[email protected]> wrote:
>
Hi
I have WLI application ( 7.0 ) and another J2EE appliction configured
on WLS (
7.0 ). If I have multiple jdbc connection pools configured to access
different
( or even the same ) databases, I am unable to get the connection to
execute a
sql query in the J2EE app. The connection pool gets initialized properly
during
the server startup and I can see them in the console but when I try to
acquire
a connection from the pool for execution of a jdbc stmt, I am unable
to obtain
a connection. Did any one succeed in configuring mulitple jdbc connection
pools
and WLI and another J2EE app to run together on WLS 7.0? Any suggestions
are welcome.
Thanks
Sreeram

Auto-Commit and Pooled JDBC Connections

Forum Members,
If I am using Oracle Pooled JDBC Connections in the OC4J container is auto-commit set to "true" by default?
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Thanks,
Richard

Richard,
Pardon me if I am stating the obvious, but you could test that in your code by invoking the getAutoCommit() method in interface java.sql.Connection.
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I'm looking at building an application using
java Servlets.
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null

Look at the Http session class in the Servlet specification. It will maintain state for you across client requests.

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Who is your ISP...?
Are you getting any error message...?
Try the following settings and check..
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Well ... It boiled down to ACLs.
"Sreeram" <[email protected]> wrote:
>
Hi
I have WLI application ( 7.0 ) and another J2EE appliction configured
on WLS (
7.0 ). If I have multiple jdbc connection pools configured to access
different
( or even the same ) databases, I am unable to get the connection to
execute a
sql query in the J2EE app. The connection pool gets initialized properly
during
the server startup and I can see them in the console but when I try to
acquire
a connection from the pool for execution of a jdbc stmt, I am unable
to obtain
a connection. Did any one succeed in configuring mulitple jdbc connection
pools
and WLI and another J2EE app to run together on WLS 7.0? Any suggestions
are welcome.
Thanks
Sreeram

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Thanks

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Try asking on the JDBC forum

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In every servlet , i connect to the database and then i close the connection, but this is not ptactical.
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Bad idea. Don't do that. The connection will timeout sooner or later (depends on DB used, it's usually around 30 mins) and your application will crash.
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