nspredicate

How do I setup a fetch request to only pull the data from an entity's attribute with one particular value? This is the basic code I've used before. -(void)fetchResults { NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:self.entityDescription.name]; NSString *cacheName = [self.entityDescription.name stringByAppendingString:@"Cache"]; // predicate code if (self.predicate != nil) { [fetchRequest setPredicate:self.predicate]; } // end of predicate code NSSortDescriptor *sortDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES]; [fetchRequest

I often use Transformable for Core Data attributes , so I can change them later. However, it seems like, if I want to use NSPredicate to find a NSManagedObject , using "uniqueKey == %@" , or "uniqueKey MATCHES[cd] %@" , it's not working as it should. It always misses matching objects, until I change the attributes of the uniqueKey of the matching object to have specific class like NSString , or NSNumber . Can someone explain the limitation of using NSPredicate with Transformable attributes? Note : I'm not sure when/if this has changed since 5/2011 (from Scott Ahten's accepted answer), but you

Consider the following NSArray: NSArray *dataSet = [[NSArray alloc] initWithObjects: [NSDictionary dictionaryWithObjectsAndKeys:@"abc", @"key1", @"def", @"key2", @"hij", @"key3", nil], [NSDictionary dictionaryWithObjectsAndKeys:@"klm", @"key1", @"nop", @"key2", nil], [NSDictionary dictionaryWithObjectsAndKeys:@"qrs", @"key2", @"tuv", @"key4", nil], [NSDictionary dictionaryWithObjectsAndKeys:@"wxy", @"key3", nil], nil]; I am able to filter this array to find dictionary objects that contain the key key1 // Filter our dataSet to only contain dictionary objects with a key of 'key1' NSString *key =

I have an NSMangedObject that contains NSSet of other NSManagedObjects . I need to check if these objects has an value in NSSet and then return them. I use MagicalRecord for fetching data. So I need something like this: NSPredicate *predicate = [NSPredicate predicateWithFormat:@"stringObjects contains %@", string]; So if NSSet stringObjects contains some string that I am looking for so then return object I have requested. One note here: stringObjects (name just for example it represent my NSSet ) it is NSSet that contains NSManagedObjects, so I need to search them by some id (for example

I'm stumped trying to write a predicate for "Recently Completed" tasks, i.e. show the task if it was completed within the last 7 days. I think I need to do something like this: "if NOW < dateCompleted + 7 days". The dateCompleted is an attribute on the table, but I'm not sure how I'm supposed to get it's value and add 7 days to it from within the predicate. I guess I need to fetch the attribute value first before writing the NSPredicate, but how? I don't have access to the managedObject at this point. This might be close the solution, but I can't figure out how to define 'oneWeek' and I don't

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: Is there a shorter way to write the format string for a predicate equivalent to this: [ NSPredicate predicateWithFormat : @ "key1 CONTAINS[cd] %@ OR key2 CONTAINS[cd] %@ OR key3 CONTAINS[cd] %@" , searchString , searchString , searchString ]; I have written a few predicate format strings like this, and I was thinking to simplify that by writing a method that takes an array of key paths and the search string to construct such a predicate. But I thought I’d ask if there is a built-in way to do this, before doing that. 回答1: