ORA-00022: invalid session ID; access denied

ORA-00022: invalid session ID; access denied

Cause: Either the session specified does not exist or the caller does not have the privilege to access it.

Action: Specify a valid session ID that you have privilege to access, that is either you own it or you have the CHANGE_USER privilege.

ORA-00021: session attached to some other process; cannot switch session

ORA-00021: session attached to some other process; cannot switch session

Cause: The user session is currently used by others.

Action: Do not switch to a session attached to some other process.

ORA-00020: maximum number of processes (string) exceeded

ORA-00020: maximum number of processes (string) exceeded

Cause: All process state objects are in use.

Action: Increase the value of the PROCESSES initialization parameter.

ORA-00019: maximum number of session licenses exceeded

ORA-00019: maximum number of session licenses exceeded

Cause: All licenses are in use.

Action: Increase the value of the LICENSE MAX SESSIONS initialization parameter.

ORA-00018: maximum number of sessions exceeded

ORA-00018: maximum number of sessions exceeded

Cause: All session state objects are in use.

Action: Increase the value of the SESSIONS initialization parameter.

ORA-00017: session requested to set trace event

ORA-00017: session requested to set trace event

Cause: The current session was requested to set a trace event by another session.

Action: This is used internally; no action is required.

ORA-00001: unique constraint (string.string) violated

ORA-00001: unique constraint (string.string) violated

Cause: An UPDATE or INSERT statement attempted to insert a duplicate key. For Trusted Oracle configured in DBMS MAC mode, you may see this message if a duplicate entry exists at a different level.

Action: Either remove the unique restriction or do not insert the key.