Can not open the user data file. Please make sure it exists, or check its permission.

无法打开用户数据文件。请确认它存在，且权限设置正确。

youdao

I do need some kind of database of users and their last timestamp, so each user will have a data file, which, for now, will contain a timestamp.

我确实需要某种类型的数据库，用于用户以及他们的最近的时间标记，所以每个用户都将拥有一个数据文件，现在其中包含有一个时间标记。

youdao

Assume that you have a single enterprise application (EAR) file that requires a database to store user data, and you have already created the schema file to populate the database.

假设您有一个企业应用程序(EAR)文件，该文件需要一个数据库来存储用户数据，您已经创建了一个架构文件来填充数据库。

youdao

Data storage, if based on the cloud, would allow the user to stream or download the file.

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