MySQL

http://schemaspy.sourceforge.net/

java -jar schemaSpy.jar -t <dbType> -db <dbName> [-s <schema>] -u <user> [-p <password>] -o <outputDir>

java -jar schemaSpy_5.0.0.jar -dbhelp

Built-in database types and their required connection parameters:
...
 mysql:
  MySQL
   -host   	hostname[:port] host where database resides with optional port
   -db   	database name
...

java -jar schemaSpy.jar -t mysql -db <dbName> [-s <schema>] -u <user> [-p <password>] -o <outputDir>