A large-scale comprehensive retail commercial enterprise mainly engaged in daily industrial products, which operates many commodity categories (Series) and has complete designs, varieties and specifications (many items) of each commodity (each commodity line). In fact, it is a complex of many professional stores. Most of them are large and medium-sized; From daily necessities to food, from industry to local products, from low-grade, middle-grade to high-grade products, it is highly comprehensive. It is a highly organized enterprise. There are commodity departments or counters inside. The commodity department is relatively independent and can be responsible for commodity purchase business, control inventory and arrange sales plans.