提取请求 - 核心数据的一些奇怪结果

Question

我有以下谓词，但是在提取请求后我得到了一些非常奇怪的结果。

谓词：

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"parkingEndTime > %f",floor(timestamp)];

示例：

• timestamp = 1 391 689 631
• 结果：1 391 689 612
• 1 391 689 625

这是完整的代码：

+ (NSArray *)getParkedCars {
    AppDelegate *myAppDelegate = [[UIApplication sharedApplication] delegate];
    NSManagedObjectContext *ctx = [myAppDelegate getThreadSafeManagedObjectContext];
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Car"];
    NSTimeInterval timestamp = [[NSDate date] timeIntervalSince1970];
    NSLog(@"Parking End Time: %f",floor(timestamp));
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"parkingEndTime > %f",floor(timestamp)];
    [request setPredicate:predicate];
    NSError *error = nil;
    NSArray *result = [ctx executeFetchRequest:request error:&error];
    NSLog(@"Fetched request: %@",[result firstObject]);
    return result;
}

Answer 1

通过在比较之前将其转换为nsnumber来修复：

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"parkingEndTime > %@",@(floor(timestamp))];