Core data sundries

• Batch operations. Streamlined insert update and delete
  • no save notifications
    • can enable persistent history to work around
  • no managed objects created
  • Basically creates a single transaction. Faster, few notification.
  • Can set an SQL upsert merge policy on context.
• Fetch only neccessary data. Batched fetching.
  • Decide if relationshsips are pre-fetched or fetched on read.
• ObjectID result type is thread safe.
  • ManagedObjects are not.
  • Dictionary results exist too, a read only data set to pass to other threads.
• CD has a lot of notifications for many updates
  • New ObjectID notification
  • NSRemoteChangeNotification. CD change notifications between processes. By using PersistentHistory.
  • Should tailor requests to the applications need, for example based on a changed date .

See also “making apps with core data”