In you application it seems the relation between the fact_table_summary and defect_type is not properly set.
I have attached a screenshot to show this fact.
In there I have used a table box to find the relation between defect_type and Source='defect_yield_op_type_summary'.
Hence that is why your results shows zero for defect_op_yield_summary field in the straight table.
Should you have further queries please feel free to ask.