Thank you, using DataContext.createDataContext() and pulling objects in with dc.localObject() looks promising! I'll test it out when I get a chance (getting sidetracked with another project).
Thanks again! On 2016-05-20 09:58 PM, Michael Gentry wrote: > Hi Brian, > > "is there any way to specify which individual objects you want to commit" > > Not really. Cayenne works at the object graph level and an ObjectContext > (or DataContext) is what is used to manage your graph changes and then > commit them in a single database transaction. > > That being said, there is nothing stopping you from creating many more > ObjectContexts and it is cheap to do so. In your example, you would: > > 1) create a brand new ObjectContext totally separate of the thread > ObjectContext, > 2) create your exception log object in that new ObjectContext, > 3) commit the new ObjectContext (which only has your exception log object > in it). > > Since you mentioned you are using 3.0.2, this is easily done with > DataContext.createDataContext(). Cayenne 3.1 requires you to get it from > the ServerRuntime. > > I'd be wary of creating children of your thread's ObjectContext for this > purpose as committing child contexts will also commit the parent, if I'm > remembering correctly. > > If your exception log object needs a relationship to an object in the > thread context, you'll either have to pull it in using DC's localObject() > method or perhaps DataObjectUtils.objectForPK(), assuming that object is > already persisted. I tend to use the latter approach, typically with the > original object's getObjectId() method. > > mrg > > > On Thu, May 19, 2016 at 12:22 PM, Brian Baillargeon <bbail...@uwo.ca> wrote: > >> Hey folks, >> >> Generally, I retrieve objects using >> BaseContext.getThreadObjectContext().performQuery(query); >> and after creating / updating / deleting objects, I commit changes with >> BaseContext.getThreadObjectContext().commitChanges(); >> >> This commits all changes on the current thread's ObjectContext, but is >> there any way to specify which individual objects you want to commit >> changes for? I'm just looking for a best practice to safeguard my >> objects, but I think this would be a valid use case: >> You have a table that logs exceptions, and you encounter an exception >> while modifying an object backed by another table. So you want to >> persist the exception's log, but not the object you were modifying. >> >> I've thought about separating my objects onto different ObjectContexts >> (Ie. children of getThreadObjectContext()), but this doesn't seem like a >> good solution, especially if you have relationships (since related >> objects have to be in the same ObjectContext). >> >> Any suggestions? I'm using Cayenne 3.0.2, but I'm all ears for 3.1 >> suggestions too. >> >> Thanks, >> Brian Baillargeon >> >>
