Versioning of message formats in a 24-hour operating environment

摘要

Method and apparatus for maintaining currency in interrelated data which is referred to but not varied by users in a multi-user system which is on-line for 24 hours a day. Reference is had to the data through a data indexing construct available to each user. Currency is maintained by adding updated elements of the data when required by changed external conditions and storing the updated elements in the multi-user system concurrently with the previous version. A new indexing construct is built for the updated data version and users are switched to the construct when access to prior data elements is no longer required. Since only a single variable relating to the indexing construct must be changed in order to switch a user, an atomic operation is utilized to perform the switching.