VSAM Essentials Workshop Training in Ireland

• describe and explain the concepts of the z/OS access methods
• analyse the structure of the RRDS, ESDS, KSDS and LDS data sets
• use the Access Method Services utility program IDCAMS to define, load, backup, monitor and manipulate VSAM data sets with particular emphasis on the KSDS file type
• develop guidelines for optimised allocation of VSAM files for use at their installation
• identify performance related issues in the batch and online environments that can be found when using the KSDS file type.

MVS and I/O processing; The access methods; The IOS Drivers; The I/O Supervisor (IOS); The Back-End process; MVS access methods; Queued Sequential Access Method; Basic Direct Access Method; Basic Partitioned Access Method; PDSE processing; And now to VSAM; VSAM features; Entry Sequenced Data Set (ESDS); Key Sequenced Data Set (KSDS); Relative Record Data Set (RRDS); Catalog concepts; ICF catalogs and VTOCS; ICF catalogs (BCS); VSAM Volume Data Set (VVDS); Cluster Catalog (BCS) entries; Alternate indexes and paths; VSAM overview - exercises.

Control Areas; Control Intervals; Control Interval structure; CI structure of fixed length records; CI structure of variable length records; Control Area structure ; elative Byte Address; Spanned records; Storage of data on DASD volumes; Entry Sequenced; Key Sequenced; Index component; Free space; RRDS characteristics; KSDS processing example; The Control Interval is rewritten; Deleting a record; Record insertion; CI split; CA split; VSAM dataset structure - exercises.

Access Method Services (AMS); AMS command format; Example - define an ESDS; Modal commands; Cancelling IDCAMS steps; Using the ELSE and SET commands; Comments; Error messages; Dataset already exists.

IDCAMS commands; DEFINE command - main parameters; Defining a cluster; Cluster sub-parameters; IDCAMS required parameters; Space allocation and reuse; SHAREOPTIONs (x region, y system); Control Interval Size; More IDCAMS parameters; DATA and INDEX sub-parameters; Defining an ESDS; Defining an RRDS; Defining a KSDS; FREESPACE; DELETE MASK | NOMASK.

Listing catalog information - LISTCAT; Catalog information; LISTCAT; LISTCAT parameters; LISTCAT examples; LISTCAT output.

VSAM data management commands; Loading datasets; REPRO; REPRO parameters; Copy ESDS to KSDS; Copy partial RRDS to RRDS; Copy keyrange from KSDS to KSDS; Merge two KSDSs; Copy KSDS to tape; Printing datasets; PRINT parameters; PRINT examples; PRINT output example - CHARACTER; Altering catalog entries; Deleting catalog entries; DELETE parameters; DELETE examples.

Why use alternate indexes?; Alternate index design; Alternate index record; Defining a route to the base cluster; Update of an alternate index; Defining an alternate index; Alternate index sub-parameters; Alternate index (SMS); AIX record size calculation; Building an alternate index; Defining a Path; Printing a base KSDS; Printing via an alternate indexes using PATH.

Data integrity; Disposition processing; VSAM SHAREOPTIONS; Cross system sharing; VSAM back-up options; The EXPORT command; VSAM recovery options; The IMPORT command.

What to tune; Record design considerations; Data CISZ and performance; CI% freespace; CI FSPC optimisation; Index CISZ considerations; Data CA size considerations; CA% freespace; Component level performance; VSAM buffers; Index component buffers; Optimum index buffering; Data component buffers; Optimum data component buffering; VSAM buffering techniques; VSAM NSR buffer utilisation; VSAM LSR buffer utilisation; Batch LSR; Is batch LSR the solution?; Batch LSR JCL changes; Additional BLSR SUBSYS parameters; BLSR recommendations; BLSR restrictions; AIX performance considerations.