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    <p>First, this isn't a SQLite error, it's a standard, basic Objective-C error. You'd have the same problem even if you weren't using a SQLite-based Core Data store.</p> <p>Let's work backward from where it looks like the error is occurring, which is:</p> <pre><code>NSDictionary *attributes = [[obj entity] attributesByName]; </code></pre> <p>You're calling <code>entity</code> on <code>obj</code>. But where did <code>obj</code> come from? From here:</p> <pre><code>[Exercises enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) { </code></pre> <p>OK, so <code>obj</code> came from <code>Exercises</code>. What is in <code>Exercises</code>?</p> <pre><code>NSArray* Exercises = [NSJSONSerialization JSONObjectWithData:[NSData dataWithContentsOfFile:dataPath] options:kNilOptions error:&amp;err]; </code></pre> <p><code>Exercises</code> is an array of things that <code>NSJSONSerialization</code> gave you. The <code>JSONObjectWithData:options:error:</code> method gives you Cocoa equivalents for the JSON content. <strong>It does not give you managed objects</strong>. In this case it looks like your JSON produced an array of <code>NSDictionary</code>.</p> <p>So what happened is:</p> <ol> <li>You used <code>NSJSONSerialization</code> and got an array of dictionaries</li> <li>You iterated over that array</li> <li>You attempted to call <code>entity</code> on the members of the array, only the array members are <code>NSDictionary</code> instances, and that class does not implement <code>entity</code>.</li> </ol> <p>Your code never creates any Core Data objects, anywhere. That's why you're not getting any Core Data objects. Your code is crashing because you're trying to call Core Data methods on objects that don't implement those methods.</p>
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    1. USTom Harrington
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    1. COHi Tom, thanks for your reply, i was first using the "ugly/crude" way to populate core data with JSON. As posted on your post in cocoa is my gf. I then tried to implement NSDictionary way to the original code that i had. How would i create a core data object "Exercises" that can be used with NSDictionary category with touchJSON. Thank you
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    2. COCreate a managed object using one of the standard ways, e.g. `[NSEntityDescription insertNewObjectForEntityForName:inManagedObjectContext:]`. My posts on CIMGF were about how to get the data from JSON to the managed object, but you still need to create the managed object first.
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    3. COCan this process be used for multiple entities? and one to many relationships?
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