NSPredicate, get results with a subset of one-to-many relationship

Question

I\'mm working around with Core Data and NSFetchedResultsController.

My Data Model looks like this:

Product with one-to-many relat

Answer 1

You should fetch the dataLine property instead. Assuming your Product and dataLine entity connected by relationship someRelation then you can try this code;

NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
[fetchRequest setEntity:[NSEntityDescription entityWithName:@"dataLine" inManagedObjectContext:self.managedObjectContext]];
[fetchRequest setPredicate:[NSPredicate predicateWithFormat:@"dataLines.week == %@",theWeek]];

NSMutableArray *tmpProduct [[NSMutableArray init] alloc];
NSMutableArray *tmpArray = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error];

for (dataLine *theDataLine in tmpArray);
NSLog(@"%@",theDataLine.someRelation.name);
tmpProduct = theDataLine.someRelation.name;

then you can just call tmpProduct to call or display your product in table view