where used list

RRM_SV_VAR_WHERE_USED_LIST_GET - for variable

RSZ_X_WHERE_USED_LIST_GET - for other component

http://www.sdn.sap.com/irj/scn/weblogs?blog=/pub/wlg/14549 - search query by element

sap bi tables

http://wiki.sdn.sap.com/wiki/display/BI/Tables+in+SAP+BW+which+give+information+related+to+Queries%2C+Work+Books+and+Web+Templates