I just started to learn mySQL. It looks like MS Access. You create tables in a database. No schema.
How should I group my tables?
Thanks.

Tables are grouped in database.
You can create more databases using "CREATE DATABASE" clause.

Thanks.
But how do I access tables in more than 1 databases in one session?
For example, in a java program I need to query tables in 2 databases.

In Oracle or db2 I can do

SELECT * FROM SCHEMA1.TABLEA join SCHEMA2.TABLEB

How to implement something like this in mySQL?

Thanks.

Yes it is possible (see GRANT clause) but keep in mind MySQL is not Oracle and your example above is not good design of database (in MySQL).