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The moose likes JDBC and Relational Databases and the fly likes Returning DB connection Big Moose Saloon
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Returning DB connection

robin singal
Ranch Hand

Joined: Jul 18, 2007
Posts: 102

I am using below method to create ad database connection where con is declared as class variable : Connection con;

Now i call this method whenever i need a db connection :

like :

And then use the con object to run queries & then close the con like:

I do this many a times in my application whenever i need to connect to db.

I need to know if if this is the right way to use the connection object.
Am I leading my application to
too many connections exception.


Life is short play hard.
Phani Raju

Joined: Aug 03, 2007
Posts: 19
It actually depends on how you intend to use the connection.

As a simple scenario, let us say you execute some queries (select/update) but only one at a time. Creating connection each time is not the right way and you can use the same connection.

You want to execute many queries simultaneously, then you can still reuse the connection provided you are doing only select queries.

Finally if the requirement is like multiple queries simultaneously, both selects and updates - yes this requires for separate connections. In this situation also you would be better off by using some kind of pooling.
[ October 17, 2008: Message edited by: Phani Raju ]
robin singal
Ranch Hand

Joined: Jul 18, 2007
Posts: 102
Hi Raju

I am using the last scenario you mentioned. I'll look at the pooling topic and try to come up with a better logic.

Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46437
Sounds a good idea; maybe better to have a close() method in your own class so you call close() rather than con.close(); this enables you to put your null checking and exception handling all in one place.

Sounds like a candidate for transfer to JDBC where this sort of topic is usually discussed.
I agree. Here's the link:
subject: Returning DB connection
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