I use Core-Data in my Iphone application. In my Core-Data I have something like that;
[object:table, number:2]
[object:table, number:4]
[object:window, number:2]
[object:window, number:5]
[object:chair, number:2]
[object:chair, number:3]
How can I get a NSArray with table's lowest number, window's lowest number and chair's lowest number? Thanks.
taken STRAIGHT from the apple website
1) specify the type of entity you want to get
NSManagedObjectContext *moc = [self managedObjectContext];
NSEntityDescription *entityDescription = [NSEntityDescription
entityForName:@"Employee" inManagedObjectContext:moc];
NSFetchRequest *request = [[NSFetchRequest alloc] init];
[request setEntity:entityDescription];
2) specify the charateristics you are looking for, (you can ignore this since you want all)
// Set example predicate and sort orderings...
NSNumber *minimumSalary = ...;
NSPredicate *predicate = [NSPredicate predicateWithFormat:
@"(lastName LIKE[c] 'Worsley') AND (salary > %@)", minimumSalary];
[request setPredicate:predicate];
3) specify the order
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc]
initWithKey:@"firstName" ascending:YES];
[request setSortDescriptors:@[sortDescriptor]];
NSError *error;
NSArray *array = [moc executeFetchRequest:request error:&error];
if (array == nil)
{
// Deal with error...
}
4) you get a sorted array so... either get the last or first entry, depending on the ordering you pick.
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