Multiple choice technology databases Which one of the following is a DL/I CALL that retrieves a unique occurrence? PCB GN GNP GHU GHNP Reveal answer Fill a bubble to check yourself D Correct answer Explanation GHU (Get Hierarchical Unique) is the DL/I call that retrieves a specific, unique segment occurrence based on a qualified SSA. GN retrieves the next occurrence, GNP gets next within a parent, but GHU uniquely identifies one segment.