Cause
string returned by PL/SQL function could not be parsed
string returned by PL/SQL function could not be parsed
fix PL/SQL function being called
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/drgus.htm
https://community.oracle.com/message/9119388
https://community.oracle.com/message/1456513
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