The perfect file to be used for these kinds of both batch and real-time processing is the Indexed Sequential Access Method (ISAM).
Indexed sequential access method (ISAM) is utilized broadly to process database activities among various stages with distinct attributes. They can be qualified by a few indexes of a representative in the one database that sequentially joined because of the data presented. A few issues in dealing with the informational collection were tended to as far as putting away, handling, and recovering of information records into the section, this because of the ailing in comprehension the ISAM sequential strategy for supervising information.
The ISAM interface blocks each consequent ISAM request investigates it to decide the identical keyed VSAM request characterizes the entered VSAM request in a request parameter rundown and starts the request.