Cause
A parallel query server lost contact with another server.
A parallel query server lost contact with another server.
Check your system for anomalies and reissue the statement. If this error persists, contact Oracle Support Services.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
https://community.oracle.com/message/9515750
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