I'm not doing anything re locking the DB, so I would imagine I would be getting default behaviour.
But if one of Activities does: db = mySQLiteOpenHelper.getReadableDatabase(); db.exexSQL(...) or db.query(...) and the IntentService does the following BEFORE the code above has managed to close the DB db2 = mySQLiteOpenHelper2.getWritableDatabase(); db2.exexSQL(...) or db.query(...) then a stacktrace is written in the logs indicating that the ReadableDatabase resources were not closed when they should have been. So then seems to be some kind of resource conflict caused by the race condition. And I'd like to avoid that. And I didn't understand your example that you suggests improves performance. It looks like you are just replacing the value of a local cursor variable with a newly constructed cursor each time. It doesn't appear that you are reusing the cursor in any way. Unless someDbAccessMethod(); is always returning the same cursor ?? But that doesn't make sense because a) it would be returning the cursor you just closed, so its no longer any good to you. b) the cursor would always return the same dataset, so I can't see how its that useful. But maybe I'm way off mark .. On Oct 19, 2:05 pm, Bret Foreman <[email protected]> wrote: > SQLite has locking on by default and you can have any number of > threads accessing it concurrently if you leave it in locking mode. > Opening and closing the database and/or the cursors is not especially > expensive. One trick that improves performance is to re-use the cursor > after you close it so the object doesn't have to be rebuilt. Something > like this: > > // cursor used here > > // Now finished with cursor > theCursor.close(); > theCursor = someDbAccessMethod(); > // More work with new cursor > > For example, I might have 5 or 6 methods in a given Activity that all > re-use the same cursor as long as I'm sure my logic does not require > two of them to use the cursor at the same time. Then the cursor object > is only created in onCreate. -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
