ORA-28523: ORACLE and heterogeneous agent are incompatible versions
Cause: An operation on a database link attempted to connect to a non-Oracle system, but the ORACLE instance and the agent process for the non-Oracle system are incompatible
Action: Ask your DBA to confirm configuration of both the ORACLE instance and the agent. Additional information on the version incompatibility is logged in trace (*.TRC) files, the ORACLE instance and the agent, and in the ORACLE instance's alert log. Check the documentation for your agent to find out which releases of the Oracle Server are supported
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