摘要:
An improved method manages the storage of document images so as to minimize the average access time while minimizing overall storage costs, consistent with the probable usage of the documents for a particular application. Document images can be selectively stored on high speed, low capacity magnetic DASD or alternately on low speed, high capacity optical storage. DASD storage is more expensive than optical storage for a document image. By characterizing the probable use of a document image in association with a case processing work flow within which the document image is to participate, optimum document storage can be achieved. When a case has a predefined plurality of document image types, and a particular document image type is missing, the case can be placed in a pending state while awaiting the receipt of the missing document image. In the pending state, the documents which are members of the pended case can be removed from the DASD and retained on the optical storage device. A notation as to the missing document type is associated with the pended case. When the missing document type is received, the case of which it is to be a member, is reactivated by accessing the existing documents for the case from the optical storage and transferring them to the DASD, along with storing the newly received missing document. The case with its full complement of documents is then made available to the user. Provision is made for prohibiting the deletion of a document image from the DASD when other active cases have that document as a member.