1 working with data sets stephen s. linkin houston community college © hccs and ibm 2008 ©hccs...

©HCCS & IBM® 2008 Stephen Linkin 1

Working With Data Sets

Stephen S. LinkinHouston Community College

© HCCS and IBM 2008

©HCCS & IBM® 2008 Stephen Linkin 2

What Is A Data Set?

The Basis For Everything Processed Records Fields

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What Is A Data Set?

Organization Sequential Partitioned VSAM

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Where Are Data Sets Stored?

Storage Drives and Media Disk (DASD) Tape (Sequential)

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What Are Access Methods?

QSAM Queued Sequential Access Method

BSAM Basic Sequential Access Method

BDAM Basic Direct Access Method

BPAM Basic Partitioned Access Method

VSAM Virtual Sequential Access Method

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DASD Terminology For UNIX And PC Users Tracks Cylinders

How Are DASD Volumes Used?

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How Are DASD Volumes Used?

What Are DASD Labels?

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Allocating A Data Set

Set Aside Space Access method services TSO ALLOCATE ISPF menus JCL

Establish A Logical Link

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How Data Sets Are Named

Unique Segmented Characters Size Conventions

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Allocating Space On DASD Volumes Through JCL

What Will We Do?

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Allocating Space On DASD Volumes Through JCL

What will we do? Logical Records And Blocks Data Set Extents

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Data Set Record Formats

F – Fixed FB - Fixed

Blocked V – Variable VB - Variable

Blocked U - Undefined

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Data Set Record Formats

Blocking BLKSIZE LRECL RECFM

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Data Set Record Formats

Blocking RECFM=FB LRECL=25

RECFM=VB LRECL=25

USA CA SAN JOSE

USA CA SAN JOSE

H 0000

H 0011

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Types Of Data Sets

What Is A Sequential Data Set? DSORG=PS

What Is A PDS?

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Types Of Data Sets

What Is A Sequential Data Set? DSORG=PS

What Is A PDS? DSORG=PO

Why Is A PDS Structured Like That? Advantages Of A PDS

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Types Of Data Sets

What Is A Sequential Data Set? DSORG=PS

What Is A PDS? DSORG=PO

Why Is A PDS Structured Like That? Advantages Of A PDS Disadvantages Of A PDS

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Types Of Data Sets

What Is A PDSE?

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Types Of Data Sets

What Is A PDSE? PDS Versus PDSE

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Types Of Data Sets

What Is A PDSE? PDS Versus PDSE

When A Data Set Runs Out Of Space

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What Is VSAM?

Data Set Type Access Method

key-sequenced entry-sequenced linear relative record

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What Is VSAM?

Control Interval Code Example

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What Is A VTOC?

Catalogs And VTOC’s

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What Is A VTOC? What Is A Catalog?

Master Catalogs And User Catalogs

Catalogs And VTOC’s

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What Is A VTOC? What Is A Catalog?

Master Catalogs And User Catalogs

Using An Alternate Master Catalog

Catalogs And VTOC’s

If IBMUSER.A1 is cataloged, then the JCL statement to allocate it to the job would be: //INPUT DD DSN=IBMUSER.A1,DISP=SHRIf it is not cataloged, the JCL statement to allocate it to a job is: //INPUT DD DSN=IBMUSER.A1,DISP=SHR,VOL=SER=WRK001,UNIT=3390

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What Is A VTOC? What Is A Catalog?

Master Catalogs And User Catalogs

Using An Alternate Master Catalog

What Is A Generation Data Group?

Catalogs And VTOC’s

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Role of DFSMS in managing space

Manual Or Automated Processes DFSMS Automates Data Set Storage Data Management Tasks

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Role of DFSMS in managing space

Allocates Space On DASD volumes. Automatically Retrieve By Name. Mount Magnetic Tape. Set Logical Connections Between

Application Programs And Their Media. Control Data Access. Transfer Data Between Applications And

Media

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z/OS UNIX File Systems

UNIX File System Is: Hierarchical And Byte-Oriented Paths and Path Names

/dir1/dir2/dir3/MyFile

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z/OS UNIX File Systems

UNIX File System Is: Hierarchical And Byte-Oriented Paths and Path Names Case Sensitive

z/OS Data Sets Vs File System Files

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Working With A zFS File System

DFS™ - Distributed File Service API - Application Program Interface SMB - Server Message Block

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Summary

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