Part explosion is the main process involved in material requirement planning (MRP), whose purpose is to generate time-phased production and purchase order information based on the master schedule, bill of materials, and inventory records. However, due to the time consuming characteristic, this process makes it difficult to use for real-time planning. To overcome this limitation, there have been many studies for improving the performance of database systems focused on the modification of the data structure, data partitioning, and materialization strategies. However, to the best of our knowledge, no attempt has yet been made to apply these advanced database technologies to the MRP part explosion process. The main contribution of this study is to improve part explosion performance by utilizing its hierarchical structure with processing queries in main memory virtual DB. The process was found to be almost 2∼5 times faster using the proposed DB schema and more than 10 times faster when the DB archiving process was performed separately. Several experimental results are shown to illustrate the performance of the proposed approach.