How do you document your mysql database tables and fields

There's two ways I create database tables:<p>- either I create them through an ORM, in which case I don't document the database tables or fields, I document the object instead.<p>- or I create it "by hand", in which case I use the standard comments to document the tables and the fields in my schema file

There are tools that can reverse-engineer tables (and relations). For example, Visio can do it for SQL Server databases.

SQL is pretty much self-documenting. But I still use hand-drawn diagrams showing how fields are related.