Document MySQL protocol databases

[dbeatty10]

Describe the feature

There are mutliple databases that are described as using the MySQL wire protocol and/or syntax including [1]:

• SingleStore
• ClickHouse
• TiDB
• PlanetScale on Vitess
• Dolt

There are probably others too. As we learn of them, it would be nice to document if any compatability testing has done against this adapter. Where applicable, redirect them to the specific adapter for the database.

Additional context

Some databases might not support crucial functionality. An example is TiDB's support for create table as ... select statements (CTAS) (#3839, #4754).

[zhangyangyu]

Hello @dbeatty10, FYI, we've developed a dbt-tidb adapter based on dbt-mysql. We've tested it against several TiDB versions and document the compatibility issues.

Thanks for your excellent work!