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On 2/13/08 1:48 PM, "Eric Polino" <[EMAIL PROTECTED]> wrote: > I've started using Cayenne a few weeks ago for our project, > www.campgroundautomation.com. In the process of working with it, I've > come across a few things I don't understand. After reading the API > and the UserGuide, can't find much to help me. > > 1. How do I count the rows of a query, without actually doing a full > blown SelectQuery and counting the elements? ie: select count(*) from > table; Various aggregate queries come up rather frequently on the list. I think someone posted a utility class at one time you could use. Otherwise, SQLTemplate will get you there. http://cayenne.apache.org/doc/sqltemplate-basics.html > 2. I've read in many places how Cayenne deals with joins for you, but > nowhere do I see an example of how its done. Here's an example > problem I'm dealing with. > > Schema: > > Reservation (n to 1) Site > Site (n to 1) > Site contains a type field > > I want to get all the Reservations of a given for a given type of > site. In sql I would execute something like, "select * from > Reservation, Site, SiteType where SiteType.Name='Something' and > Site.typeID = SiteType.id and Reservation.siteID = Site.id" > > Short of writing an parameterized sql string and executing that in my > code, how do I do that with Cayenne? I hope I explained all that well > enough...make sense? Just map the relationships in the modeler. Cayenne takes care of the SQL for you. The following guide should help you get started with the modeler: http://cayenne.apache.org/doc20/tutorial-starting-mapping-project.html -- Kevin
