Method and system for order fulfillment in a distribution center

A computer-implemented method of fulfilling an order, the method using a distribution center having a plurality of sites for storing a plurality of items, the method comprising:

• receiving an order designating items and quantities of items;
• identifying a first site which has the highest number of items in the order, and the items in the order that are available from the first site;
• determining the items remaining in the order after removing those items identified as being available from the first site;
• and
• identifying a second site which has the highest number of the items remaining in the order, and the items remaining in the order that are available from the second site,
• wherein the method further comprises retrieving at least one item identified from one of the sites, with the retrieval of the at least one item being dependent on an expiration time associated with the at least one item,
• wherein the center has at least two major sites,
• wherein at least one item in the order is located in a first major site and at least one item in the order is located in a second major site,
• wherein the first site and the second site are in the first major site, and
• wherein the method is implemented by at least one computing device,
• wherein for two major sites, items at one major site are stored at a higher humidity than items at the other major site.