Hi, I got the answer right by luck after multiple trials, but I still dont understand why. At the begining, I was referring 'po_items'table for the FROM as the question asks to find the 'item_ids' in the 'po_items' table, however it kept showing error. After looking at the data tables I realized there's no 'descr' column in it which caused the error everytime, but why it's still shown in the question since we never use 'po_items'in SQL enqury? Much appreciate if you could explain, cheers!