What version are you on? This is for Psql 2000. It is for a BOM three components deep, but you will get the idea if you have more.
Cut and paste this query:
SELECT BMPRDSTR.PARENT_ITEM_NO, BMPRDSTR.COMPONENT_ITEM_NO, BMPRDSTR.QTY_PER_PARENT, BMPRDSTR_1.PARENT_ITEM_NO AS Level2Parent, BMPRDSTR_1.COMPONENT_ITEM_NO AS Level2Component, BMPRDSTR_1.QTY_PER_PARENT AS Level2QTY_PER_PARENT, BMPRDSTR_2.PARENT_ITEM_NO AS Level3Parent, BMPRDSTR_2.COMPONENT_ITEM_NO AS Level3Component, BMPRDSTR_2.QTY_PER_PARENT AS Level3QTY_PER_PARENT
FROM (BMPRDSTR LEFT JOIN BMPRDSTR AS BMPRDSTR_1 ON BMPRDSTR.COMPONENT_ITEM_NO = BMPRDSTR_1.PARENT_ITEM_NO) LEFT JOIN BMPRDSTR AS BMPRDSTR_2 ON BMPRDSTR_1.COMPONENT_ITEM_NO = BMPRDSTR_2.PARENT_ITEM_NO;
That might get you started. Use grouping in your report to total components.
Kirk