Just a snippet from my Certification studies:
//Commerce Cache handling
//cache invalidation time is configured in ecf.[objecttype].config
//e.g. ecf.catalog.config element
CatalogCache.Clear(); //clears the entire catalog cache
CatalogCache.Remove(“entrykey”); //invalidate a specific entry
CustomersCache.Clear(); //clear all customers cache
MarketingCache.Clear();
OrderCache.Clear();
SecurityCache.Clear();