1 Working With Data Sets Stephen S. Linkin Houston Community College © HCCS and IBM 2008 ©HCCS & IBM® 2008 Stephen Linkin

2 What Is A Data Set?  The Basis For Everything Processed Records Fields

©HCCS & IBM® 2008 Stephen Linkin3 What Is A Data Set?  Organization Sequential Partitioned VSAM

©HCCS & IBM® 2008 Stephen Linkin4 Where Are Data Sets Stored?  Storage Drives and Media Disk (DASD) Tape (Sequential)

©HCCS & IBM® 2008 Stephen Linkin5 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

©HCCS & IBM® 2008 Stephen Linkin6  DASD Terminology For UNIX And PC Users Tracks Cylinders How Are DASD Volumes Used?

©HCCS & IBM® 2008 Stephen Linkin7 How Are DASD Volumes Used?  What Are DASD Labels?

©HCCS & IBM® 2008 Stephen Linkin8 Allocating A Data Set  Set Aside Space Access method services TSO ALLOCATE ISPF menus JCL  Establish A Logical Link

©HCCS & IBM® 2008 Stephen Linkin9 How Data Sets Are Named  Unique  Segmented  Characters  Size  Conventions

©HCCS & IBM® 2008 Stephen Linkin10 Allocating Space On DASD Volumes Through JCL  What Will We Do?

©HCCS & IBM® 2008 Stephen Linkin11 Allocating Space On DASD Volumes Through JCL  What will we do? Logical Records And Blocks Data Set Extents

©HCCS & IBM® 2008 Stephen Linkin12 Data Set Record Formats  F – Fixed  FB - Fixed Blocked  V – Variable  VB - Variable Blocked  U - Undefined

©HCCS & IBM® 2008 Stephen Linkin13 Data Set Record Formats  Blocking BLKSIZE LRECL RECFM

©HCCS & IBM® 2008 Stephen Linkin14 Data Set Record Formats  Blocking RECFM=FB LRECL=25 RECFM=VB LRECL=25 USACA SAN JOSE USACA H 0000 H 0011

©HCCS & IBM® 2008 Stephen Linkin15 Types Of Data Sets  What Is A Sequential Data Set? DSORG=PS  What Is A PDS?

©HCCS & IBM® 2008 Stephen Linkin16 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

©HCCS & IBM® 2008 Stephen Linkin17 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

©HCCS & IBM® 2008 Stephen Linkin18 Types Of Data Sets  What Is A PDSE?

©HCCS & IBM® 2008 Stephen Linkin19 Types Of Data Sets  What Is A PDSE? PDS Versus PDSE

©HCCS & IBM® 2008 Stephen Linkin20 Types Of Data Sets  What Is A PDSE? PDS Versus PDSE  When A Data Set Runs Out Of Space

©HCCS & IBM® 2008 Stephen Linkin21 What Is VSAM?  Data Set Type  Access Method key-sequenced entry-sequenced linear relative record

©HCCS & IBM® 2008 Stephen Linkin22 What Is VSAM?  Control Interval  Code Example

©HCCS & IBM® 2008 Stephen Linkin23  What Is A VTOC? Catalogs And VTOC’s

©HCCS & IBM® 2008 Stephen Linkin24  What Is A VTOC?  What Is A Catalog? Master Catalogs And User Catalogs Catalogs And VTOC’s

©HCCS & IBM® 2008 Stephen Linkin25  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=SHR If 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

©HCCS & IBM® 2008 Stephen Linkin26  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

©HCCS & IBM® 2008 Stephen Linkin27 Role of DFSMS in managing space  Manual Or Automated Processes  DFSMS Automates Data Set Storage  Data Management Tasks

©HCCS & IBM® 2008 Stephen Linkin28 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

©HCCS & IBM® 2008 Stephen Linkin29 z/OS UNIX File Systems  UNIX File System Is: Hierarchical And Byte-Oriented Paths and Path Names /dir1/dir2/dir3/MyFile

©HCCS & IBM® 2008 Stephen Linkin30 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

©HCCS & IBM® 2008 Stephen Linkin31 Working With A zFS File System  DFS™ - Distributed File Service  API - Application Program Interface  SMB - Server Message Block

©HCCS & IBM® 2008 Stephen Linkin32 Summary  Read The Redbook