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POCore Data, try to use NSPredicate to filter a toMany relationship set but get the "to-many key not allowed here" error
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copied!<p>Here is the model I have: <a href="http://www.girardet.ch/model.png" rel="noreferrer">http://www.girardet.ch/model.png</a></p> <p>My goal is to retrieve all the Quotes with these criterias:</p> <ul> <li>belong to a specific theme : the name_en attribute of Themes</li> <li>order by relevancy</li> <li>filtered by Authors (with the alias attribute of Authors)</li> </ul> <p>Here is my code:</p> <pre><code>NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"ThemeEntries" inManagedObjectContext:_context]; [fetchRequest setEntity:entity]; NSSortDescriptor *sortDescriptor1 = [[NSSortDescriptor alloc] initWithKey:@"relevancy" ascending:NO]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor1, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; // predictate - filter NSPredicate *predicate = [NSPredicate predicateWithFormat:@"theme.name_en=%@ AND quotes.author.alias=%@",@"mytheme", @"myauthor"]; </code></pre> <p>[fetchRequest setPredicate:predicate];</p> <p>I get the "to-many key not allowed here" error.</p> <p>If I instead use this predicate</p> <pre><code>NSPredicate *predicate = [NSPredicate predicateWithFormat:@"theme.name_en=%@, @"mytheme"]; </code></pre> <p>it works well and I can loop over the <code>ThemeEntries</code> that I get and get all my quotes... But it's not filtered by authors.</p> <p>What can I do to filter by Authors?</p>

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