> On 29.10.2009, at 20:05, Ben Trumbull wrote: > >>> I get a "Could not merge changes"-error on save in a single moc app >>> (*). The docs state this is a problem of a multi-moc setup: >>> >>> http://developer.apple.com/mac/library/documentation/Cocoa/Conceptual/CoreData/Articles/cdTroubleshooting.html >>> >> >> Yes, the MOC you are saving refers to data that has changed out from >> underneath it in either the PSC or the database file itself. This >> is an optimistic concurrency control failure. >> >>> The error does not appear on every system and seems to be related to >>> when save is called. (race condition?) So far I only have users >>> complaining that run Mac OS 10.6. I can rarely reproduce the error >>> myself. >>> >>> Any pointers where to look? >> >> Well, you can break on -[NSManagedObjectContext init], and -save: to >> see if you really only have 1 MOC. Other than that, breaking on + >> [NSError errorWithDomain:code:userInfo:] and doing "thread apply all >> bt" in gdb is usually helpful. >> >>> >>> I use garbage collection. >>> >>> regards >>> Ruotger >>> >>> (*) the context is handed out by a singleton method. I NSAssert() >>> this >>> method is only called by the main thread. >> >> Well, it's still possible for code to leak it to another thread if, >> you say, pass NSManagedObjects around, and then ask them for their >> MOC. >> >> - Ben > > Hi, > > I've checked all accesses to the moc and by using mogenerator I > generated files that assert that every single access of a managed > object is on the main thread. I still get the "Could not merge data"- > error or sometimes this one:
Which is neither here nor there. This is a version conflict error not a multi-threading error (though MT errors can lead to versioning errors) > Printing description of error: > Error Domain=NSCocoaErrorDomain Code=1550 UserInfo=0x5d45490 "balances > is not valid." > > balances is a one-way to multiple relation. > > Any more ideas? Same as last time, break on the error, get it's userInfo, and a stack trace of all the threads in the app. - Ben _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
