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Third Edition (Auguest 2022)
This edition applies to z/OS Version 1 Release 13 DFSMS (product number 5694-A01).
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Preface
Virtual Storage Access Method (VSAM) is one of the access methods used to process data. Many of us have used VSAM and work with VSAM data sets daily, but exactly how it works and why we use it instead of another access method is a mystery.
This book helps to demystify VSAM and gives you the information necessary to understand, evaluate, and use VSAM properly. This book also builds upon the subject of Record Level Sharing and DFSMStvs. It clarifies VSAM functions for application programmers who work with VSAM. The practical, straightforward approach should dispel much of the complexity associated with VSAM. Wherever possible an example is used to reinforce a description of a VSAM function.
This IBM Redbooks publication is intended as a supplement to existing product manuals. It is intended to be used as an initial point of reference for VSAM functions.
The team who wrote this book
This book was produced by a team of specialists from around the world working at the International Technical Support Organization, Poughkeepsie Center.
Mary Lovelace is a Consulting IT Specialist at the International Technical Support Organization. She has experience with IBM in large systems, storage and Storage Networking product education, system engineering and consultancy, and system support. She has written IBM Redbooks about Tivoli Storage Productivity Center, Tivoli Storage Manager, Scale Out Network Attached Storage, and IBM z/OS storage products.