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    <p>I just ran into a crash on update, and it appears that the <code>newIndexPath</code> is provided as an index path into the fetched results controller objects when that index path does not match the index path needed to retrieve the cell from the table. Consider the following:</p> <ol> <li>A table view has a section at index 0 with 15 items.</li> <li>The item at index 13 (the second-to-last item) is deleted</li> <li>The item at index 14 (the last item) is updated</li> </ol> <p>In the above case, assuming that you are using <code>[tableView beginUpdates]</code> and <code>[tableView endUpdates]</code> in the appropriate <code>controllerWill/DidChangeContent:</code> methods, you will need to use the <code>indexPath</code> parameter to retrieve the cell from the table to update (which will be section 0, index 14) and the <code>newIndexPath</code> parameter to retrieve the object to configure the cell with from the results controller (which will be section 0, index 13).</p> <p>I assume it works this way because the delete seems to have already happened as far as the results controller is concerned, but has not happened in the table view (due to the <code>beginUpdates/endUpdates</code> calls wrapping the updates). It makes some sense if you consider the above case, but it seems that all of the documentation does not consider this case.</p> <p>So the answer to the question is that it appears that you should use the <code>indexPath</code>parameter to retrieve a cell from the table view, and the <code>newIndexPath</code> parameter to retrieve the object from the fetched results controller. Note that if there has not been an insert or delete it appears to pass <code>nil</code> for <code>newIndexPath</code>, so in this case you would have to use <code>indexPath</code> for both purposes.</p>
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    1. POHow to use newIndexPath for NSFetchedResultsChangeUpdate?
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    1. USCharles A.
    1. USCharles A.
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    1. COUpon further reflection, it seems to me that the NSFetchedController should be calling the delegate method with a move event instead of an update event. It does this in the simple test case I just created. It's a mystery to me at the moment what condition triggers an update instead.
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    2. COIf you read the article I linked to in the question you should see that it is exactly what I did.
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    3. COMy mistake, I didn't actually see the link until you pointed it out. What line of code is causing the crash in your case? Which NSIndexPath are you using and what are you doing with it?
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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