Patent ID: 8639590

Claim:
A computer-implemented method of checking the availability of products, the method comprising: receiving information, by a processor, on a plurality of first electronic data sets, each first data set including a first key and further including a product quantity in relation to a single point of time or time period, said first key including a primary key element and a plurality of secondary key elements, said primary and secondary key elements representative of product-related conditions; deriving, by the processor, information on one or more second electronic data sets, each second data set including a second key and further including product quantities in relation to a series of points of time or time periods, said second key exclusively formed of said secondary key elements; receiving, by the processor, a query including a product quantity for one or more products; and checking, by the processor, said information on said one or more second electronic data sets against one or more product-related checking requirements to derive result information on whether the product quantity for the one or more products given in the query is available, wherein said information on said one or more second data sets is availability-to-promise stacks, the availability-to-promise stacks are filled based on exploding said information on said first data sets while the availability-to-promise stacks are filled, and no direct-access data container allowing indexed access to its content is generated from the first data set before filling the availability-to-promise stacks.