See inverted list.
In computing, a file that reorganizes the structure of an existing data file to enable a rapid search to be made for all records having one field falling within set limits.
For example, a file used by an estate agent might store records on each house for sale, using a reference number as the key field for sorting. One field in each record would be the asking price of the house. To speed up the process of drawing up lists of houses falling within certain price ranges, an inverted file might be created in which the records are rearranged according to price. Each record would consist of an asking price, followed by the reference numbers of all the houses offered for sale at this approximate price.