File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
http://aspose.com/file-tools
The moose likes JDBC and the fly likes ResultSet Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login


Win a copy of The Java EE 7 Tutorial Volume 1 or Volume 2 this week in the Java EE forum
or jQuery UI in Action in the JavaScript forum!
JavaRanch » Java Forums » Databases » JDBC
Bookmark "ResultSet" Watch "ResultSet" New topic
Author

ResultSet

phani kon
Ranch Hand

Joined: Apr 06, 2005
Posts: 251
What is the other alternative method for finding the number of records in the result set without using
while(rs.next)
{
;;
}
Stan James
(instanceof Sidekick)
Ranch Hand

Joined: Jan 29, 2003
Posts: 8791
I think JDBC deliberately did not give us an API for that because it would force the resultset to retrieve all the rows for counting. The number could be high enough to be a serious performance drag. Under normal use the resulset retrieves some number of rows at a time as you move the cursor into them, but not all of at once.

A common suggestion is to run one query to select count and another to select the rows.

What do you want to do with the total number? Maybe we can figure out a way to live without it.


A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi
phani kon
Ranch Hand

Joined: Apr 06, 2005
Posts: 251
Thanks for your reply. But do you have any other method like scrollable result set..?
Stan James
(instanceof Sidekick)
Ranch Hand

Joined: Jan 29, 2003
Posts: 8791
There are probably some SQL tricks ... select an extra computed column that is row number and sort descending so the first row has the row count. I'd still be more interested in making the requirement for row count go away.
 
Don't get me started about those stupid light bulbs.
 
subject: ResultSet