Tag Archives: featured

Mainframe

COBOL

Mainframe: The Complete COBOL Course From Beginner To Expert

Follow @tutorial_brain

Introduction of COBOL

COBOL stands for Common Business Oriented Language.
It is started in 1959 by CODASYL committee (Conference on Data Systems Language).
COBOL programs appear like an ENGLISH language.
COBOL can handle a huge volume of data.
ANSI (American National Standards Institute) worked further on improving this and major development took place in improvement in the year 1965 and 1974.
The improved version of COBOL was introduced in 1985, with new features.

Example of COBOL Program

IDENTIFICATION DIVISION.
PROGRAM-ID. HELLOWRD.

PROCEDURE DIVISION.
DISPLAY “SIMPLE HELLO WORLD”.
STOP RUN.

Output

SIMPLE HELLO WORLD

Where, How and Why we use COBOL

In Mainframe COBOL is one of the most important programming languages
COBOL is a programming language and we use it in multiple industries like Retail, Healthcare, Insurance, Banking, Share Market, Finance and much more.
And it is like the English language so it is self-documenting
We can use 30years older COBOL code till now and run without any changes in modern Mainframe server.
COBOL is a procedural language and works well in legacy applications.
Lots of COBOL programmers are retired and this is a great opportunity for a fresher to learn COBOL to land a dream job.
Most of the fortune 500 companies use Mainframe and COBOL is the most preferred programming language is always a ‘MUST TO HAVE’ skills for a Mainframe Developer.

Target audience

This tutorial is for anyone, be in a student, a software engineer or anyone who is serious towards mastering the COBOL programming on Mainframe.
If you have prior knowledge on any topic, then you can skip that topic which you are already familiar with based on your requirement.
Most of the Mainframe Developers face a problem of low-quality content lying on the Internet and this tutorial will certainly help them.

Prerequisite and Requirements

If you have a mainframe id, it is an advantage to learn COBOL but it is not mandatory.
You can practice COBOL using OPEN COBOL IDE as well.
We don’t need any previous coding language to learn COBOL.
If you know basic TSO/ISPF and JCL, it will always help you to master COBOL programming fastly. Don’t worry, we have added TSO and JCL tutorial as well in our website, you can go through them.

What will you learn

This COBOL tutorial starts from basics like Introduction of COBOL, Structure of COBOL and covers everything in detail.
Our COBOL tutorial contains a lot of examples and Coding.
This tutorial tries to show all the examples based on a real-world scenario.
The programs explained in this tutorial is compiled and ran without any errors.
The Quality and Quantity of the tutorial are great. The contents of this tutorial are explained by expert Mainframe Developers.

Mainframe

JCL

Introduction of JCL

JCL stands for Job Control Language.
A Scripting language is used to communicate with the MVS operating system.
Use JCL to run jobs on MVS operating systems.
We can use JCL to perform a set of a task in steps or sequence
Divided into various types of statements and parameters.
A COBOL program will run through JCL.
JCL provides all the resource and information such as the file names, a location of the file, associated file name, compiled module location, statements, parameters and much more.
JCL will run in a Batch mode we will cover this topic as we progress further.

Example of a JCL

//CREATEPS JOB (345),’TUTORIALBRAIN,CLASS=A,MSGCLASS=A,MSGLEVEL=(1,1),
// NOTIFY=&SYSUID
//************************************************************
//* ALLOCATE PS DATA SET USING IEFBR14 UTILITY
//************************************************************
//STEP10 EXEC PGM=IEFBR14
//SYSPRINT DD SYSOUT=*
//SYSOUT DD SYSOUT=*
//SYSDUMP DD SYSOUT=*
//DD1 DD DSN=MATEKS.TEST.PS,
//DISP=(NEW,CATLG,DELETE),
//SPACE=(TRK,(1,1),RLSE),
//UNIT=SYSDA,
//DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=800)
//*

We can use JCL to create a new PS file

Follow @tutorial_brain

Where, How and Why we use JCL

JCL is the most important Scripting language used to run COBOL on Mainframe.
JCL is very easy scripting language and it provides all the options to execute a COBOL program.
There are multiple utilities which help in executing tasks in an easier and better way.
All these utilities will be shown in detail in this tutorial
It is easy to tweak changes to a JCL and hence the learning curve in JCL is easy.
JCL runs in Batch mode. A Batch mode is a mode where the user or system submits a job(series of task) through a JCL and the JCL runs in Background allowing the user to perform any other task while the JCL is running. Hence, JCL is a widely used scripting language for COBOL because it enables multitasking in Mainframe through Batch processing.

Target audience

This tutorial is for anyone, be in a student, a software Engineer or anyone who is serious towards mastering the JCL scripting language in Mainframe.
If you have prior knowledge on COBOL, then it will help you to understand JCL better but this is not important and you can still learn JCL easily without any prior understanding of any programming language.
Most of the Mainframe Developers face a problem of low-quality content on JCL lying on the Internet and this JCL tutorial will certainly help them.

Prerequisite and Requirements

If you have a mainframe id, it is an advantage to learn JCL but it is not mandatory.
No Previous programming language in any other language is required to learn JCL if you have experience with COBOL, it is advantageous.
If you know basic TSO/ISPF, it will always help you to master JCL easily. Don’t worry, we have added a TSO/ISPF tutorial as well in our website, you can go through them.

What will you learn

This JCL tutorial covers almost everything starting from Introduction, structure, syntax, all statements, parameters, procedures, GDG’s, Utilities and much more.
In this tutorial, you will learn each topic with a lot of examples to make learning easier for students.
We are continuously adding and improving the content of this tutorial.
Expert Mainframe developers are monitoring this site to provide quality content.

Mainframe

VSAM Tutorial

Welcome to the VSAM Tutorial!!!

This tutorial will take your journey from absolute beginner to the advanced level so this Tutorial is a combination of – ‘VSAM tutorial for beginners’ as well as ‘VSAM tutorial for Experienced’.

Most of the Training institutes charge you a minimum of $100 USD for VSAM Training but you can master complete VSAM tutorial for free.

Introduction of VSAM files

VSAM stands for Virtual Storage Access Method.
VSAM files are datasets which are NOT sequential Files.
Virtual Storage Access Method is an IBM DASD file Storage method.
The records in a VSAM file can be of Fixed Length or a variable Length.

When You Should Choose a VSAM file over normal Sequential file?

When you want to do multiple operations in the file based on a particular key value, then you should choose a VSAM file.
If you want to update a particular record in the file or you want to delete your files as a normal activity, then you choose VSAM(Virtual Storage Access Method) file over sequential file because your intention is to perform multiple operations on the file.
VSAM files are much more powerful and advanced as compared to normal sequential files.
You can access the records of Sequential file in sequential order only but you can access the records of a VSAM file in multiple ways based on your requirement. You can access the records sequentially or using a key or dynamically in case of VSAM files.
There are multiple types of VSAM files and you can select the VSAM file based on your requirement.
When simple operations are involved like reading the file, writing the output to SPOOL(Simultaneous Peripheral Operations Online) or output device, then you can use sequential files but suppose you need a file wherein you need to frequently change the contents of the file periodically and multiple operations are required like different way of accessing etc. then you can use VSAM files.
If your file has a particular key value, then you can use that key value to access the records. You can access the records using primary key or even alternate keys.
If you need to update, insert or delete the records frequently, then VSAM is a better option compared to sequential files.
If you want to access the file directly using IPSF options 3.4, then VSAM is not a good choice.
You have to see the performance issues as well.

Follow @tutorial_brain

Important points about a VSAM file

You cannot directly modify the VSAM file using ISPF or using option 3.4 of TSO/ISPF.
VSAM files cannot access the data stored in Tape but can access the data from or to a DASD(Direct Access Storage Device).
The Records can be accessed in multiple ways like sequential order or you can also place the records in a logical sequence using a primary or secondary key or you can also access the records in random order or you can also access the records using RRN(Relative Record Number).

What will you learn in this Tutorial?

Complete VSAM Tutorial
Learn what is VSAM(Virtual Storage Access Method.
When you should use VSAM
We will start with the Introduction of VSAM files up to complete advanced levels.
Master the Data and Index Component of VSAM
You will learn about the Data and Index component of all the VSAM files.
Alternate Index
How to access the record using an alternate key?
How to delete an alternate index file?
Important functions of VSAM file
You will be able to change the properties of the VSAM file?
We will show you on How to print the records

Audience

Anyone who is a beginner on Mainframe with a basic knowledge of TSO/ISPF can learn easily from this tutorial.
The student or the learner should have basic knowledge of JCL(Job Control Language).
If you have basic knowledge of COBOL, it will be an added advantage while learning VSAM tutorial but it is not mandatory.

Introduction of COBOL​

Example of COBOL Program

Output

Where, How and Why we use COBOL

Target audience​

Prerequisite and Requirements​

What will you learn​

Introduction of JCL

Example of a JCL

Where, How and Why we use JCL

Target audience​

Prerequisite and Requirements​

What will you learn

Introduction of VSAM files

When You Should Choose a VSAM file over normal Sequential file?

Important points about a VSAM file

What will you learn in this Tutorial?

Audience

Tutorials for all brains!

Introduction of COBOL

Target audience

Prerequisite and Requirements

What will you learn

Target audience

Prerequisite and Requirements