VSAM Programming & Optimization
 

This 4 day course is intended for:

Application Programmers, System Programmers and technical personnel who will be working with VSAM file Structures. Techniques are presented to help the student to determine VSAM Cluster and Alternate Index (AIX) file: optimization, reorganization, processing and loading.  Students are encouraged to being LISTCAT listing and descriptions of current and proposed VSAM file/AIX files to be evaluated.  Students will learn how to effectively DEFINE, BUILD and process VSAM objects for use in the batch and on-line environments.

Topics Covered:

• Introduction to VSAM
• VSAM Data set and Data Organizations
• Catalogs and JCL
• Physical Organization
• Processing, Performance and Optimization
• Calculating DASD Space
• AMS: Defining Data Sets
• Alternate Index (AIX) and Path
• Basic SMS and VSAM
• Other AMS Commands
• COBOL Processing
   

Objectives:

Case studies will be used as a continuity point for students to tie all aspects of VSAM file processing from start to finish.  A z/OS and OS/390 platform will be used to run class problems coded by the students.

Duration: 4 days

Delivery: Class Lecture and Hands-on Labs

Audience: 

Application developers, System programmers, file designer and technical personnel that are involved with developing, maintaining and monitoring VSAM file structures.

Prerequisites:

It is strongly recommended that the student

• Have at least 1 year of programming experience
   (Able to code a program, in their language, from scratch)
• Understand IBM's Job Control Language (JCL)
   (Able to code enough JCL to run and compile a program that they have written.)
• Have experience in TSO, ISPF or its equivalent
   (Able to use the editor to edit, browse and review application code and output)

Outline:

1. Introduction to VSAM

 VSAM Terminology
 VSAM Dataset types and objects
 VSAM Comparisons
 Control Interval - Basic Layouts
 Relative Byte Address (RBA)
 General Organization of KSDS, ESDS, RRDS and LDS
 Alternate Index, Path and Base Cluster

2. VSAM Data set and Data Organizations

 Linear Datasets (LDS)
 Relative Record Data Sets (RRDS)
 Entry Sequenced Data Sets (ESDS)
 Key-Sequenced Data Sets (KSDS)
 Spanned Records

3. Catalogs and JCL

 Types of Catalogs
 Catalog Searching
 Master and User Catalogs
 Defining a User Catalog
 Defining an ALIAS
 Accessing VSAM Data Sets
 The AMP parameter

4. Physical Organization

 DASD
 Count-Key-Data
 Fixed Block Architecture (FBA)
 Physical Records

5. Processing, Performance and Optimization

 KSDS
 KSDS Index
 Record Insertion Strategies
 Optimization
 Buffers

6. Calculating DASD Space

 Factors effecting DASD space
 Control Area (CA) size
 Control Interval (CI) size
 Index Key Compression
 CI Utilization efficiency
 Free Space
 Space Calculations - ESDS & RRDS
 Space Calculations - KSDS
 KSDS - Data Component
 KSDS - Index Component

7. AMS: Defining Data Sets

 Batch JCL to Define VSAM objects
 Coding Syntax and Rules
 Coding Examples
 MODAL Commands
 MODAL Command Examples
 Defining Clusters (DEF CL) - Syntax, Required and Optional Parameters
 Alternate Index (AIX) and Path
 Alternate Indexes
 DEFINE ALTERNATEINDEX (DEF AIX) - Syntax, Required and
       Optional Parameters
 Estimating Disk Space for an AIX
 Steps for Building the Alternate Index
 BULDINDEX (BIX) - Syntax, Required and Optional Parameters
 PATH (DEF PATH) - Syntax, Required and Optional Parameters
 Upgrade Set

8. Basic SMS and VSAM

 SMS and JCL
 AVGREC, DATACLAS, STORCLAS, MGMTCLAS, SECMODEL,
 LIKE and REFDD
 RECORG and KEYOFF

9. Other AMS Commands

 REPRO - Syntax, Required and Optional Parameters
 DELETE - Syntax, Required and Optional Parameters
 LISTCAT - Syntax, Required and Optional Parameters
 ALTER - Syntax, Required and Optional Parameters
 PRINT - Syntax, Required and Optional Parameters
 GENERATIONDATAGROUP (GDG) - Syntax, Required and
       Optional Parameters

10. COBOL Processing

 Defining Extended VSAM Return Code Support
 VSAM Return Code
 VSAM Function Code
 VSAM FEEDBACK Code - Logical and Physical Errors
 COBOL Processing using RRDS - Environment, Data and
       Procedure Division Coding
 COBOL Processing using ESDS - Environment, Data and
       Procedure Division Coding
 COBOL Processing using KSDS and AIX - Environment, Data and
       Procedure Division Coding