Indexed File Organization
For an indexed file, the system retrieves records based on the content of specified key fields. APPX requires one primary key field for each file and optionally permits up to 16 alternate keys.
Key fields, when used by the system to retrieve records, are referred to as key paths. This method of record retrieval is inherently slower than the method employed for sequential files but is more flexible and allows you to perform more sophisticated processing operations.
An indexed file can contain an unlimited number of records, subject only to restrictions imposed by available storage space and operating system limitations. Unlike records in a sequential or a one-record file, you can directly change or delete records from indexed files, even if they are of variable length.
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