This is permitted if alternate keys are specified as allowing duplicates. Calling the Routine To illustrate how to use the routine, the COBOL fragments below are taken from the one of the suite of test programs I used as I developed the routine all of which may be downloaded from this page.
Deletion of records is not possible in ESDS dataset. It utilizes virtual storage concept and can protect datasets at various levels by giving passwords.
So duplication of records is not possible. VSAM provides fast access to data sets. The record length is set to For relative files, records are accessed in the order of the relative record numbers.
Key value is searched in the index component. This provides random access and assumes the application program has a way to get the desired record numbers. Records in an ESDS file can be accessed sequentially.
Each record in the data component of a KSDS cluster contains a key field with same number of characters and occur in the same relative position in each record. You may use them as examples to see how to set up the parameter block for the various combinations of organization, access, and open mode.
There are three types of file organisation you can use with VSAM.