add document reader database TiDB

[sincerity-being]

我们鼓励使用英文，如果不能直接使用，可以使用翻译软件，您仍旧可以保留中文原文。另外请按照如下要求提交相关信息节省社区维护同学的理解成本，否则该讨论极有可能直接被忽视或关闭。
We recommend using English. If you are non-native English speaker, you can use the translation software. In addition, please submit relevant information according to the following requirements to save the understanding cost of community maintenances, otherwise the discussion is very likely to be ignored or closed directly.

Which Component
eg. Nacos Discovery, Sentinel

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Describe the solution you'd like
A clear and concise description of what you want to happen.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature regexRequest here.