Supporting Multiple Oracle Clients I have an application where the data repository is moving to Oracle 11g.  This means we need the new Oracle 11g client on the application server to support the retrieval of their data. 

Is it possible to have both the Oracle 10 and Oracle 11 clients running on the same server? 

If not, can the Oracle 11 client support retrieval of data from an Oracle 10 database?
Yes, you can run multiple clients on one machine. It's mainly a case of making sure you set your ORACLE_HOME correctly before starting any work.

But you can talk to 10 DBs using the 11 client happily, so that would also work for you.