Counting records in a database when criteria querying

AleBrozzo · **Posted:** Tue Jul 18, 2006 2:28 pm

Is there a way to find out the number of records that match a specified criteria without fetching the data? I need this to implement paging in my web app: the user can search filtering by some properties, but could also just hit the "search" button without entering any filters, which would end retrieving every record in a large table.
Please keep in mind that I'm using Citeria querying, not HQL.

Thanks for trying to answer me!
Alejandro

tenwit · **Joined:** Thu Dec 23, 2004 9:08 pm **Posts:** 2008

Set the criteria's projection to Projections.rowCount().

AleBrozzo · **Posted:** Wed Jul 19, 2006 9:09 am

Your answer is a good guidance, but still I can't solve the problem. I found in JIRA an issue that is supposed to solve this problem:

http://jira.nhibernate.org/browse/NH-617?page=all

I downloaded the code and put it into the NHibernate project. It didn't compile, but all errors where in a single cs file (AbstractEmptynessExpression.cs). I tried to fix them, I guess the problem was with the NH version because some of the errors where regarding namespaces and differences in names. I couldn't fix them all, so I just erased the file, and voilà, the project compiled. Yet, I can't add the projection to the criteria nor I can find an exaple of how to use this...

Help!!!

Also: I'm using NH 1.0.2.0, is this the latest stable version?

Alejandro.

nokiola · **Joined:** Sun Jun 19, 2005 2:21 pm **Posts:** 21

Hello,

By the way... for which version of NHibernate is the projections code from JIRA and how do I integrate it into NHibernate so that I can access something like this:

Code:

IList results = session.createCriteria(typeof(AnObject)) .setProjection(Projections.projectionList()
.add(Projections.rowCount())).list(); 

Regards,
Robert