ALTERING GDG DEFINITION 5. DELETING GDG 6. IMPORTANT PRACTICAL QUESTIONS 1. INTRODUCTION Generation Data Groups or GDGs are a group. This facility is called Generation Data Groups (GDG). . There are two types of mainframe processes: Batch Processing Online Transaction Processing. JCL & VSAM: Hi all, I want to know the major difference between the dataset and GDG. reagrds akshatha.

Author: Shakam Necage
Country: Azerbaijan
Language: English (Spanish)
Genre: Spiritual
Published (Last): 2 January 2012
Pages: 117
PDF File Size: 5.15 Mb
ePub File Size: 9.77 Mb
ISBN: 442-8-14587-230-5
Downloads: 92654
Price: Free* [*Free Regsitration Required]
Uploader: Mezimi

Copyright IBM Corporation This section includes links to documents with additional information that are beyond the scope and purpose of this document.

The documentation and software were developed and tested on systems that are configured for a SIMOTIME environment based on the hardware, operating systems, user requirements and security requirements. It is provided “AS IS” without any expressed or implied warranty, including the implied warranties of merchantability, fitness for a particular purpose and non-infringement. The operating system is able to keep the generations in chronological order.

Quite often, to reach larger markets or provide a higher level of service to existing customers it requires the newer Internet technologies to work in a complementary manner with existing corporate mainframe systems.

JCL Defining Datasets

SimoTime Technologies shall not be liable for any direct, indirect, special or consequential damages resulting from the loss of use, data or projects, whether in an action of contract or tort, arising out of or in connection with the use or performance of this software, documentation or training material. We reserve the right to make changes without notice at any time.

Hence, the dataset is deleted when gcg job completes execution. Therefore, adjustments may be needed to execute the jobs and programs when transferred to a system of a different architecture or mainrame. If the attributes and organizations of all generations in a group are identical, the generations or individual data sets may be retrieved together as a single data set.


The input used by this suite of programs is generated within mainfrane programs. The preceding job should be used with mainfrzme. Generation data sets have sequentially ordered absolute and relative names that represent their age. Outdated or obsolete generations can be automatically deleted by the operating system.

Delete a Generation Data Group. All of the data sets in the group can be referred to by a common name. In a standardised JCL, the program to be executed and its related datasets are placed within a cataloged procedure, which is called in the JCL. JCL, Execute the Jobs. Before you create the files that attach to a GDG base you may want to create a model dataset that contains the DCB information for the files.

For new non-system-managed data sets, if you do not specify a volume and the data set is not opened, the system does not catalog the data set.

JCL – Defining Datasets

If you have any questions, suggestions, comments or feedback please call or send an e-mail to: The preceding job that is described in Step 8 created an output file. GV00 and so on. The maximum number of generations that you can associate with a base is GDG is created as the output. Since the DSN name is the GDG name without an appended GnnnnVnn segment each of the individual data sets or files will be processed as a contiguous file starting with mwinframe last created data set.

This document and the links to other documents are intended to provide a greater awareness of the Data Management and Application Processing alternatives. An initial model DCB can be defined to be used by all versions, but it can be overridden when creating new versions.

A typical sequence of events is to submit the jobs described in Steps to Enterprise Server and then review the results. New system-managed data sets are always cataloged when allocated, with the volume assigned from a storage group.


Delete Functions, Use with Caution. We have a team of individuals that understand the broad range of technologies being used in today’s environments. The intent is to provide changes as the need arises and in a timeframe that is dependent upon the availability of resources.

We specialize in the creation and deployment of business applications using new or existing technologies and services. SimoTime Technologies was founded in and is a privately owned company. We specialize in preparing applications and the associated data that are currently residing on a single platform to be distributed across a variety of platforms. The DSN parameter refers to the physical dataset name of a newly created or existing dataset.

A SimoTime License is required for the items to be made available on a local system or server. Define a GDG Base. Our customers include small businesses using Internet technologies to corporations using very large mainframe systems. The individual files within a group have a generation number added to the end of the name to make each file name unique. The program was tested using Micro Focus Net Express, version 5.

A generation data group GDG base is allocated in a catalog before the generation data sets are cataloged.

What is a GDG?

This is called Backward Referencing. The data will need to be transferred between the mainfrxme and may need to be converted and validated at various stages within the process. SimoTime has the technology, services and experience to assist in the application and data management tasks involved with doing business in a multi-system environment.

Submit the jobs described in steps and review the results.