3167067 - ETL failed with FINAL_CASE_ATTR Case type/Error executing TransformationProcessor CASE in SAP Signavio Process Intelligence

When running transformation and load, I get an error as below. 

Case type: FINAL_CASE_ATTR

Message: Error executing TransformationProcessor CASE - (The field 'c_caseid' contains null values)

Please make sure there are no NULL values for c_caseid, c_eventname and c_time are filtered from your resulted queries.

For Event collectors:

WHERE c_caseid IS NOT NULL AND c_eventname IS NOT NULL AND c_time is NOT NULL

For Case attributes:

WHERE c_caseid IS NOT NULL

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