- Entity エンティティの creationDate 属性に作成日時が入っているものとして、今日作成されたデータを取得する場合
NSCalendar* calendar = [NSCalendar currentCalendar];
unsigned int flags = NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay;
NSDateComponents* components = [calendar components:flags fromDate:[NSDate date]];
NSDate* fromDate = [calendar dateFromComponents:components];
NSDate* toDate = [fromDate dateByAddingTimeInterval:60*60*24];
NSPredicate* p = [NSPredicate predicateWithFormat:@"(creationDate >= %@) AND (creationDate < %@)", fromDate, toDate];
Entity* entity = [Entity MR_findFirstWithPredicate:p];