jQuery in Action, 3rd edition
The moose likes JDBC and Relational Databases and the fly likes Closing Statement. Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Databases » JDBC and Relational Databases
Bookmark "Closing Statement." Watch "Closing Statement." New topic

Closing Statement.

Costa lamona
Ranch Hand

Joined: Sep 24, 2006
Posts: 102

I am new to jdbc, closing a Statement is releasing its resources, I am wondering if this will include closing the connection itself.
also If I am connecting to localhost db,
Is creating a new Connection will be costy?
Is creating new Statement will be costy?


Jeanne Boyarsky
author & internet detective

Joined: May 26, 2003
Posts: 33102

Hi Costa,
Closing a statement will not close the connection because a connection is a higher level concept. Closing a connection will sometimes close a statement but you should not rely on this.

Creating a connection is usually relatively costly. This is why people use connection pools. Creating a statement is not costly and a frequent operation.

[OCA 8 book] [Blog] [JavaRanch FAQ] [How To Ask Questions The Smart Way] [Book Promos]
Other Certs: SCEA Part 1, Part 2 & 3, Core Spring 3, TOGAF part 1 and part 2
Bauke Scholtz
Ranch Hand

Joined: Oct 08, 2006
Posts: 2458
Assuming that you're using a decent JDBC driver, closing a statement will only close any opened resultsets and closing a connection will close any opened statements and indirectly also its opened resultsets.

Obtaining a connection is the most expensive task in JDBC. You can improve performance by using connection pooling. When you're developing a webapplication, it's good to know that most self-respected application servers offers JNDI connection pooling out of the box. When you're developing a client application, then you may need to add connection pooling libraries so that you can make use of it. Commonly used ones are Apache Commons DBCP, C3P0 and Proxool
I agree. Here's the link: http://aspose.com/file-tools
subject: Closing Statement.
It's not a secret anymore!