Hi Jeff, A couple more thoughts...
It's worth noting that I don't get the error when I use the hierarchical values approach without lazy loading, and get my films info from my actor objects. > Thanks for this info. The performance problem is most likely due to the > fact that FDMS is fetching the list of films for each actor... this is > the lazy loading issue we have currently that I mentioned in a previous > post. If we were to follow the hibernate model more closely, we'd send > "actor" instances to the client without having populated the list of > films for each actor at all. The first "get" call made on the films > property for a given actor would then go back to the server and fetch > them. As it is now, we'll do one query to retrieve the list of actors, > then a query for each actor to get its list of films. For a large DB, > this is a lot of queries to do. > This is a pretty high priority feature request. For now, the workaround > would be to modify your domain model so there is an intermediate object > but that is awkward when you are generating everything from the simple > schema. I'm not sure that I understand this. I believe that I have "an intermediate object" - filmActor.java and filmActor.as. Are you suggesting that I use that object - or rather those objects - as a way of finding out what filmIds are related to an actorId? I.e. that I load them from their own destination? I'm tired so if this isn't clear, don't worry about it. :-) Do I understand correctly that until we get the fix lazy loading isn't necessarily going to solve any performance problems? Douglas Jeff Vroom wrote: > > Thanks for this info. The performance problem is most likely due to the > fact that FDMS is fetching the list of films for each actor... this is > the lazy loading issue we have currently that I mentioned in a previous > post. If we were to follow the hibernate model more closely, we'd send > "actor" instances to the client without having populated the list of > films for each actor at all. The first "get" call made on the films > property for a given actor would then go back to the server and fetch > them. As it is now, we'll do one query to retrieve the list of actors, > then a query for each actor to get its list of films. For a large DB, > this is a lot of queries to do. > > This is a pretty high priority feature request. For now, the workaround > would be to modify your domain model so there is an intermediate object > but that is awkward when you are generating everything from the simple > schema. > > As to why it is not working, from the output, the "filmId" of each Film > object is getting sent to the client as a "null" value. I am not sure > why... I can't tell if it is retrieving the values from the database as > null or if FDMS is just not getting the values from the objects > properly. It could have something to do with the "short" data type - I > do not think we've tried id properties as short values so maybe > something is getting messed up because of that? It might be worth > changing that to an int if that is an easy test to run. > > I will try to get a chance to look at this more tomorrow. > > Jeff > > -----Original Message----- > From: [email protected] <mailto:flexcoders%40yahoogroups.com> > [mailto:[email protected] > <mailto:flexcoders%40yahoogroups.com>] On > Behalf Of Douglas McCarroll > Sent: Wednesday, November 29, 2006 11:26 AM > To: [email protected] <mailto:flexcoders%40yahoogroups.com> > Subject: Re: [flexcoders] many-to-many managed association in Hibernate > destination > > Jeff Vroom wrote: > > > 4) If you turn on debug logging in the server for > > the "Endpoint.*" logging category, you'll see the > > object graph which is sent to the client after > > your fill. I am curious if the time is being > > spent loading the data from the database or > > sending data to the client, or a combination of > > both. > > Okay, I've figured out how to do this part. Results here: > > http://www.brightworks.com/technology/tech_questions/hibernate_lazy_asso > <http://www.brightworks.com/technology/tech_questions/hibernate_lazy_asso> > ciations/debug_log_01.txt > > > If you can also turn on debug logging of the SQL > > that hibernate is using that would help figure out > > if we are just fetching too many objects or what. > > It looks as though I do this by adding a line to > HibernateManager.java... > > public void createSessionFactory(Configuration hibernateConfig, > boolean useTransactions) throws ExceptionInInitializerError > { > try > { > > New Line -> hibernateConfig.setProperty("hibernate.show_sql", "true") > > sessionFactory = hibernateConfig.buildSessionFactory(); > > Yes? > > BTW, in case someone finds this someday with Google, here are some > resources: > > FDS Logging: > > http://livedocs.macromedia.com/flex/2/docs/wwhelp/wwhimpl/common/html/ww > <http://livedocs.macromedia.com/flex/2/docs/wwhelp/wwhimpl/common/html/ww> > help.htm?context=LiveDocs_Parts&file=00001112.html > > http://weblogs.macromedia.com/dharfleet/archives/2006/08/debugging_flex. > <http://weblogs.macromedia.com/dharfleet/archives/2006/08/debugging_flex.> > cfm > > http://tech.groups.yahoo.com/group/flexcoders/message/56192 > <http://tech.groups.yahoo.com/group/flexcoders/message/56192> > > Hibernate Logging: > > http://www.javalobby.org/java/forums/t44119.html > <http://www.javalobby.org/java/forums/t44119.html> > > -- > Flexcoders Mailing List > FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt > <http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt> > Search Archives: > http://www.mail-archive.com/flexcoders%40yahoogroups.com > <http://www.mail-archive.com/flexcoders%40yahoogroups.com> > Yahoo! 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