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ORA-00723:

Initialization parameter COMPATIBLE must be explicitly set
Cause: Oracle detected that the initialization parameter COMPATIBLE was not explicitly specified, and the compatibility of the database is lower than the default value of the COMPATIBLE parameter. In order to use the new compatible setting, the intialization parameter must be explicitly set by the user.
Action: Explicitly set the value of COMPATIBLE parameter either in PFILE or SPFILE, whichever is used.