z/OS VSAM and Access Method Services

z/OS VSAM and Access Method Services

Course code: SS83G

Duration: 4 Days

Prerequisite:

You should complete:
•    z/OS Facilities (ES15)
•    z/OS Job Control Language and Utilities (ES07) or
•    Fundamental System Skills in z/OS (ES10)
•    or have equivalent experience

Course Description:

This course is designed to teach how to manage VSAM and non-VSAM data sets by coding and using the functions and features of the Access Method Services program, IDCAMS.

Course Objectives:

•    Understand the structure and use of VSAM data sets or clusters
•    Code IDCAMS commands to define and load VSAM clusters
•    Code IDCAMS commands to define and load alternate indexes
•    Code IDCAMS commands to list, alter, and delete catalog entries
•    Code IDCAMS commands to print data sets
•    Calculate the Direct Access Storage Device (DASD) space requirements for VSAM clusters
•    Code the Job Control Language (JCL) for IDCAMS and programs which process VSAM clusters
•    Use IDCAMS and JCL options to improve the performance of a VSAM job
•    Reorganize, back up, and recover VSAM and non-VSAM data sets
•    Interpret an IDCAMS listing of an Integrated Catalog Facility (ICF) catalog
•    Select and use the appropriate documentation to utilize VSAM and IDCAMS

Intended Audience:

This is an intermediate course for individuals who manage data sets using IDCAMS and VSAM.

Course Outlines:

Introduction to VSAM data sets
•    describe the structure, organization, and use of VSAM clusters
•    explain the function of Control Intervals (CI) and Control Areas (CA)
•    describe the purpose of CI splits and CA splits and how they are accomplished
•    estimate DASD space requirements for various cluster types

ICF catalogs
•    discuss the use of the ICF catalog
•    describe the structure, purpose, and basic contents of the master catalog

•    describe how the master catalog is located at initial program load (IPL) time
•    discuss the structure, purpose, and basic contents of user catalogs
•    create the ICF catalogs
•    describe the catalog search
•    discuss and create the two types of alias

IDCAMS commands, part 1
•    discuss the IDCAMS program
•    code the JCL to run IDCAMS
•    code the DEFINE CLUSTER command to create specific VSAM data set organizations
•    code the LISTCAT command to format and print entries from the catalog

JCL for VSAM
•    explain creation and deletion of VSAM clusters using JCL and the DFSMS data class facility
•    describe the additional JCL parameters that support VSAM clusters
•    discuss the purpose of data class
•    explain the assignment of data class through JCL and the Automatic Class Selection (ACS) routines

IDCAMS commands, part 2
•    describe the function of REPRO, PRINT and DELETE commands
•    use REPRO to load and back up a VSAM cluster
•    use PRINT to print a VSAM cluster in various formats
•    use DELETE to remove the catalog entry for the data set and scratch the data set from the volume
•    describe and code modal commands to provide for conditional execution of Access Method Services (AMS) statements

Buffering
•    explain how buffer space may impact performance either positively or negatively
•    explain the use of data and index buffers in sequential processing and direct processing
•    evaluate the use of JCL Access Method Parameters (AMP) keywords to manage buffers
•    code the buffer keywords on the Dataset Definition (DD) statement

VSAM integrity and security
•    explain how integrity and security is maintained
•    discuss the meaning and use of SHAREOPTIONS
•    discuss the need for serialization of updates to a data set
•    describe how ENQ/DEQ macros are used to serialize data set updates in multiregion and multisystem environments

•    explain the impact of buffering and SHAREOPTION modifications
•    explain VSAM record level sharing
•    use the VSAM integrity and security options: RECOVERY, ERASE, VERIFY, and passwords
•    compare VSAM passwords with Resource Access Control Facility (RACF) security

Tuning
•    explain the use of CI and CA FREESPACE
•    discuss the performance impact of cache
•    describe the space allocation process with KEYRANGES and multivolume data sets
•    explain the contents of an Index CI
•    explain how VSAM key compression works

IDCAMS ALTER
•    explain the basic functions of the ALTER command
•    code the ALTER command to modify options for processing existing VSAM objects
•    code the ALTER command to modify options for buffering, FREESPACE, SHAREOPTIONS and passwords

Alternate indexes
•    describe the reasons for using an alternate index
•    discuss the basic contents of an alternate index
•    use a PATH to process base cluster records directly and in alternate key sequence
•    define and load an alternate index
•    explain the impact of SHAREOPTIONS when opening a base cluster and associated alternate indices
•    explain programming and JCL considerations

Advanced functions and extended format data sets
•    explain VSAM advanced functions, extended format data sets, and their major features
•    explain data stripping
•    explain compression
•    explain multivolume allocation options
•    explain extended addressability
•    explain system managed buffering
•    explain partial space release
•    explain space constraint relief

Data set reorganization, backup, and recovery
•    describe the need for data set backup
•    explain the advantages and disadvantages of REPRO
•    explain the advantages and disadvantages of EXPORT / IMPORT
•    explain the advantages and disadvantages of DFSMS Data Set Services (DFSMSdss) DUMP / RESTORE
•    explain the advantages and disadvantages of DFSMS Hierarchical Storage Management (DFSMShsm) HBACKDS / HRECOVER
•    discuss backup frequency
•    determine when reorganization is required
•    code the AMS commands for backup, recovery, and reorganization

Linear Data Sets (LDS)
•    describe Data-In-Virtual (DIV)
•    explain the structure and use of LDS
•    explain the use of the DIV macro to access LDS
•    discuss candidates for LDS

Management and problem analysis aids
•    explain the use of the DCOLLECT command to gather management and planning information about the storage subsystem
•    discuss tools used to identify and trace VSAM errors
•    code the AMS EXAMINE command to test the structure of a Key Sequenced Data Set (KSDS)
•    interpret EXAMINE output to determine how to recover from a KSDS structural error
•    invoke the Generalized Trace Facility (GTF) to track VSAM-related events
•    invoke utilities to print GTF trace output

Local and global shared resources
•    explain techniques to conserve virtual storage by sharing buffers and control blocks
•    discuss the concept of shared resource pools
•    discuss the advantages and disadvantages of Local Shared Resources (LSR)
•    discuss the advantages and disadvantages of Global Shared Resources (GSR)
•    describe macros that control use and allocation of shared resources
•    discuss how to specify and monitor shared buffer allocation in CICS and Information Management System (IMS)

CICS VSAM recovery
•    describe the major functions of CICS VSAM recovery
•    explain the concept of transaction processing, backup, and recovery
•    explain how to implement and manage CICS VSAM recovery

Application coding considerations
•    describe VSAM processing terminology
•    define various VSAM processing options
•    explain the merge of catalog entries, JCL parameters, and program definitions that determine processing options
•    discuss VSAM programming support, and JCL requirements in Common Business Oriented Language (COBOL), Programming

Language One (PL/I), and Assembler languages
•    describe JCL and programming requirements for COBOL, PL/I, and Assembler languages