Client reported the"I-QO051: Output is invalid (ORA-936). Contact Target Sofware for assistance." error after making an update to one of their outputs.
The issue was that the SQL syntax in the output for the a field had a null after (+)=. In the example provided, Telephone Number had the T2.PREFERRED_TELEPHONE(+) =. The resolution was to update the syntax to be T2.PREFERRED_TELEPHONE(+) = 'Y'.