I'm not sure about its use in JPA, but it can be done in general by fully qualifying the schema.table in queries. It will only work if the user has access to all schemas. It's not a good idea though, and the only time I have needed to do it, we found it easier to import the table temporarily, run the queries and drop the table.
Joined: Oct 31, 2007
i tried the same way you said i was able to execute that query in oracle but while mapping to my entity i am wrong somewhere. could you provide me a example for joining two tables with object relational mapping.