Relative Files
All three access modes are allowed.
In the sequential access mode, the sequence in which records are accessed is the ascending order of the relative record numbers of all records that currently exist within the file.
In the random access mode, you control the sequence in which records are accessed. The desired record is accessed by placing its relative record number in a RELATIVE KEY data item; the RELATIVE KEY must not be defined within the record description entry for this file.
In the dynamic access mode, you may change from sequential access to random access, using the appropriate forms of input-output statements.