iphone - 从 select sqlite 命令转换为 NSPredicate

Question

我有这条选择线。

[TableProperties setObject:[NSString stringWithFormat:@"username='%@' AND id IN (SELECT  Max(id) FROM messages GROUP BY MD5) ",MobilyUserAccount] forKey:@"tableWhere"];

我想将此选择行更改为。

NSPredicate *findUser = [NSPredicate predicateWithFormat:@"username='%@' AND id IN (SELECT  id==max(id) FROM messages GROUP BY MD5)",MobilyUserAccount];

当我让应用程序运行时，我有这个错误。

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Unable to parse the format string "username='%@' AND id IN (SELECT  id==max(id) FROM messages GROUP BY MD5)"'

请我需要帮助将第一行转换为。

NSPredicate *findUser = [NSPredicate predicateWithFormat]

谢谢大家