dispatch_queue and core data

Question

I know that NSManagedObjectContext is not thread safe but I want to execute my fetches and updates in the background. So I have questions on if I can do this.

I have one singleton that accesses the core data stuff so I wanted to create a serial dispatch_queue_t can execute all the requests in serial. Is this okay cause I am not sure if all the requests will be executed in the same thread but there will not be any concurrent operations since it is serial.

[Core Data **is** thread safe](http://stackoverflow.com/a/21941891/10673). The `NSManagedObjectContext` is just thread contained. The terminology is important. — Marcus S. Zarra, Mar 07 '14 at 19:26

dariaa · Accepted Answer · 2014-03-07T19:43:30.623

10

There is no need in creating serial dispatch_queue_t just trust NSManagedObjectContext to handle it, just use performBlock: & performBlockAndWait:

    [context performBlock:^{
        // do fetches or updates here and do not worry about threads,
        // just make sure your context has a proper concurrencyType
    }];

edited Mar 07 '14 at 19:43

answered Mar 07 '14 at 16:43

dariaa

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To be clear, @dadougster is correct, you shouldn't pin an `NSManagedObjectContext` to a serial queue because the serial queue doesn't guarantee thread confinent. – Heath Borders Mar 08 '14 at 04:16

dispatch_queue and core data

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