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POCoreData gets emptied after adding data into it
 

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  1. POCoreData gets emptied after adding data into it
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    <p>I have a CoreData entity <code>Tracker</code> which stores the dates. The app receives a notification and the <code>CheckListViewController</code> enters data in CoreData for up to 13 days, so when the CheckListViewController gets dismissed, the CoreData entity <code>Tracker</code> will be filled with 13 rows.</p> <p>In the <code>MainViewController</code> (which dismisses <code>CheckListViewController</code>), I have the following code:</p> <pre><code> - (void)dataSaved { self.checkListVC dismissViewControllerAnimated:YES completion:^{ // fetching all the data from 'Tracker' entity and doing NSLog on it // all data gets logged in console without any issues }]; } </code></pre> <p>Now, after that somewhere in my code, I fetch all the data from the entity <code>Tracker</code> but the return data is empty. The CoreData doesn't show any error it simply returns and empty array.</p> <p>Edit: Code to fetch results from CoreData</p> <pre><code>NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:ENTITY]; NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"date" ascending:NO]; [request setSortDescriptors:@[sortDescriptor]]; request.predicate = (fromDate &amp;&amp; toDate) ? [NSPredicate predicateWithFormat:@"date &gt;= %@ AND date &lt;= %@", fromDate, toDate] : nil; __block NSArray* fetchedHabits; [managedObjectContext performBlockAndWait:^{ NSError *error = nil; fetchedHabits = [managedObjectContext executeFetchRequest:request error:&amp;error]; if (error) NSLog(@"Unknown error occurred while fetching results from CoreData, %@ : %@", error, [error userInfo]); }]; </code></pre> <p>CoreData model: <img src="https://i.stack.imgur.com/l1nxA.png" alt="enter image description here"></p> <p><strong>Update 1</strong>: So as you can see there are two entities, namely <code>Habit</code> and <code>Tracker</code>. When I fetch results from <code>Habit</code> it all works fine, but when I try to fetch results from <code>Tracker</code> it gives me an empty array. I have a common <code>NSManagedObjectContext</code> instance because you can manage multiple CoreData entities with single <code>managedObjectContext</code>. I have checked <code>managedObjectContext.persistentStoreCoordinator.managedObjectModel.entitiesByName</code> and it also lists both the entities.</p> <p><strong>Update 2</strong>: Code where I add data in to <code>Tracker</code></p> <pre><code>TrackerCoreData *tracker = [NSEntityDescription insertNewObjectForEntityForName:ENTITY inManagedObjectContext:managedObjectContext]; tracker.date = date; tracker.habits = habits; // saving CoreData explicitly NSError *error = nil; [managedObjectContext save:&amp;error]; </code></pre>
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    1. USnefarianblack
    1. USnefarianblack
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    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. COcan you show code how you are saving objects in coredata.
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      1. USaahsanali
    2. COAdded fetch code
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      1. POCoreData gets emptied after adding data into it
      1. USnefarianblack
    3. COIt would be nice to see the code you use to save the objects.
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      1. USFiro
 

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