[Java] How to implement cross database queries similar to presto

### Describe the usage question you have. Please include as many useful details as possible.

The document explanation is not very clear. If I want to cross database query and join two datasets through Arrow, how to do it, how to implement the language layer, Arrow memory format data, how to obtain other services, and through a web server?

### Component(s)

Java

首先审阅现有的 Arrow Java 文档及其关于跨数据库查询的指导。明确所请求的工作是文档编写还是实现方案；要完成这项工作，需要为语言层、Arrow 内存处理、服务访问和 Web 服务器集成确定具体范围。

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