The logical model is an arrangement of domain objects. Often, these domain objects have a strong presence in the database. That is, a domain object is easily recognizable as a relational table. But domain objects also include relationships and that's where the divergence with and RDBMS begins.
For example, take a simple domain object called 'Contact'. The Contact can be any of three ContactTypes: Customer, 'C'; Vendor, 'V'; or Employee, 'E'. Also, a Contact may at least one email address. In a logical model, this is shown as follows in a diagram created in Enterprise Architect.
|CONTACT Logical Model|
|CONTACT Physical Model|
There are some techniques in Java that can bridge this gap. Look for future posts identifying easy-to-use or graphical solutions to integration.