I read much about Core Data.. but what is an efficient way to make a count over an Entity-Type (like SQL can do with SELECT count(1) ...). Now I just solved this task with s
I'll just add that to make it even more efficient... and because its just a count, you don't really need any property value and certainly like one of the code examples above you don't need sub-entities either.
So, the code should be like this:
int entityCount = 0;
NSEntityDescription *entity = [NSEntityDescription entityForName:@"YourEntity" inManagedObjectContext:_managedObjectContext];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
[fetchRequest setEntity:entity];
[fetchRequest setIncludesPropertyValues:NO];
[fetchRequest setIncludesSubentities:NO];
NSError *error = nil;
NSUInteger count = [_managedObjectContext countForFetchRequest: fetchRequest error: &error];
if(error == nil){
entityCount = count;
}
Hope it helps.