It is possible to method to exchange ERD diagram in one tool with other as XMI is available for swapping UML documents?
The nearest factor I know of to this is actually the Common Warehouse Metamodel (CWM), that has support from some tool suppliers. The state specs lives Here. Data modelling is really a subset of the - it is going into mappings too. Just like specifications created by committee it's comprehensive, verbose and most likely very difficult to implement.
A less complicated method which will enable you to get a few of the way there's to export the schema as SQL, run it right into a scratch database and reverse engineer it using the new tool. This can, however, often lose comments or any attached documentation. With respect to the tools, you might have the ability to bodge something together to save this.
For instance, after i designed a python script that will interpret the SQL output from Visio Enterprise Architect to create MIF files for any data dictionary document. The output has got the table and column paperwork inside a format that's simple to parse and connect with column definitions. If you're able to programatically place your comments ought to in to the repository of the destination tool you could utilize an identical way of migration.