Dynamic Call Cobol Program

COBOL Quick Guide. COBOL Quick Guide. Dynamic Call Cobol Program' title='Dynamic Call Cobol Program' />If you have an interesting story to share, please post an answer, but do not abuse this question for bashing a language. We are programmers, and our primary tool. COBOL Overview. Introduction to COBOLCOBOL is a high level language. One must understand the way COBOL works. Computers only understand machine code, a binary stream of 0s and 1s. COBOL code must be converted into machine code using a compiler. Run the program source through a compiler. The compiler first checks for any syntax errors and then converts it into machine language. The compiler creates an output file which is known as load module. This output file contains executable code in the form of 0s and 1s. Evolution of COBOLDuring 1. In 1. 95. 9, COBOL was developed by CODASYL Conference on Data Systems Language. The next version, COBOL 6. In 1. 96. 8, COBOL was approved by ANSI as a standard language for commercial use COBOL 6. It was again revised in 1. COBOL 7. 4 and COBOL 8. In 2. 00. 2, Object Oriented COBOL was released, which could use encapsulated objects as a normal part of COBOL programming. QSAM FILE STATUS 90 Check the DD statement and the SELECT. QSAM FILE STATUS 91 Attempting to process a closed file. QSAM FILE STATUS 92 Probable user error. Code, Example for Program for Banking Application in C Programming. In COBOL, a native character set is the default character set that comes with the computer specified in the OBJECTCOMPUTER paragraph. In IBMs Virtual. Q. What are DB2 Storage Areas When you write COBOL Programs, that read data records from Files, and store Output results to a File, you must declare Input and Output. Importance of COBOLCOBOL was the first widely used high level programming language. It is an English like language which is user friendly. All the instructions can be coded in simple English words. COBOL is also used as a self documenting language. COBOL can handle huge data processing. COBOL is compatible with its previous versions. COBOL has effective error messages and so, resolution of bugs is easier. Features of COBOLStandard Language. COBOL is a standard language that can be compiled and executed on machines such as IBM AS4. Business Oriented. COBOL was designed for business oriented applications related to financial domain, defense domain, etc. It can handle huge volumes of data because of its advanced file handling capabilities. Robust Language. COBOL is a robust language as its numerous debugging and testing tools are available for almost all computer platforms. Structured Language. Logical control structures are available in COBOL which makes it easier to read and modify. COBOL has different divisions, so it is easy to debug. COBOL Environment Setup. Try it Option Online. Game Hacked Websites. We have set up the COBOL Programming environment online, so that you can compile and execute all the available examples online. It gives you confidence in what you are reading and enables you to verify the programs with different options. Feel free to modify any example and execute it online. Try the following example using our online compiler available at Coding. Ground. IDENTIFICATION DIVISION. PROGRAM ID. HELLO. PROCEDURE DIVISION. DISPLAY Hello World. For most of the examples given in this tutorial, you will find a Try it option in our website code sections at the top right corner that will take you to the online compiler. So just make use of it and enjoy your learning. Installing COBOL on WindowsLinux. There are many Free Mainframe Emulators available for Windows which can be used to write and learn simple COBOL programs. One such emulator is Hercules, which can be easily installed on Windows by following a few simple steps as given below Download and install the Hercules emulator, which is available from the Hercules home site www. Once you have installed the package on Windows machine, it will create a folder like C herculesmvscobol. Run the Command Prompt CMD and reach the directory C herculesmvscobol on CMD. The complete guide on various commands to write and execute a JCL and COBOL programs can be found at www. Hercules is an open source software implementation of the mainframe System3. ESA3. 90 architectures, in addition to the latest 6. Architecture. Hercules runs under Linux, Windows, Solaris, Free. BSD, and Mac OS X. A user can connect to a mainframe server in a number of ways such as thin client, dummy terminal, Virtual Client System VCS, or Virtual Desktop System VDS. Every valid user is given a login id to enter into the ZOS interface TSOE or ISPF. Compiling COBOL Programs. In order to execute a COBOL program in batch mode using JCL, the program needs to be compiled, and a load module is created with all the sub programs. The JCL uses the load module and not the actual program at the time of execution. The load libraries are concatenated and given to the JCL at the time of execution using JCLLIB or STEPLIB. There are many mainframe compiler utilities available to compile a COBOL program. Some corporate companies use Change Management tools like Endevor, which compiles and stores every version of the program. This is useful in tracking the changes made to the program. COMPILE JOB ,CLASS6,MSGCLASSX,NOTIFY SYSUID. STEP1 EXEC IGYCRCTL,PARMRMODE,DYNAM,SSRANGE. SYSIN DD DSNMYDATA. URMI. SOURCESMYCOBB,DISPSHR. SYSLIB DD DSNMYDATA. URMI. COPYBOOKMYCOPY,DISPSHR. SYSLMOD DD DSNMYDATA. URMI. LOADMYCOBB,DISPSHR. SYSPRINT DD SYSOUT. IGYCRCTL is an IBM COBOL compiler utility. The compiler options are passed using the PARM parameter. In the above example, RMODE instructs the compiler to use relative addressing mode in the program. The COBOL program is passed using the SYSIN parameter. Copybook is the library used by the program in SYSLIB. Executing COBOL Programs. Given below is a JCL example where the program MYPROG is executed using the input file MYDATA. URMI. INPUT and produces two output files written to the spool. COBBSTEP JOB CLASS6,NOTIFY SYSUID. STEP1. 0 EXEC PGMMYPROG,PARMACCT5. STEPLIB DD DSNMYDATA. URMI. LOADLIB,DISPSHR. INPUT1 DD DSNMYDATA. URMI. INPUT,DISPSHR. OUT1 DD SYSOUT OUT2 DD SYSOUT SYSIN DD CUST1 1. CUST2 1. 00. 1. The load module of MYPROG is located in MYDATA. URMI. LOADLIB. This is important to note that the above JCL can be used for a non DB2 COBOL module only. Executing COBOL DB2 programs. For running a COBOL DB2 program, a specialized IBM utility is used in the JCL and the program DB2 region and required parameters are passed as input to the utility. The steps followed in running a COBOL DB2 program are as follows When a COBOL DB2 program is compiled, a DBRM Database Request Module is created along with the load module. The DBRM contains the SQL statements of the COBOL programs with its syntax checked to be correct. The DBRM is bound to the DB2 region environment in which the COBOL will run. This can be done using the IKJEFT0. JCL. After the bind step, the COBOL DB2 program is run using IKJEFT0. DBRM library as the input to the JCL. STEP0. 01 EXEC PGMIKJEFT0. STEPLIB DD DSNMYDATA. URMI. DBRMLIB,DISPSHR. SYSPRINT DD SYSOUT SYSABOUT DD SYSOUT SYSDBOUT DD SYSOUT SYSUDUMP DD SYSOUT DISPLAY DD SYSOUT SYSOUT DD SYSOUTSYSTSPRT DD SYSOUT SYSTSIN DD DSN SYSTEMSSID. RUN PROGRAMMYCOBB PLANPLANNAME PARMparameters to cobol program. LIBMYDATA. URMI. LOADLIB. In the above example, MYCOBB is the COBOL DB2 program run using IKJEFT0. Please note that the program name, DB2 Sub System Id SSID, and DB2 Plan name are passed within the SYSTSIN DD statement. The DBRM library is specified in the STEPLIB. COBOL Program Structure. A COBOL program structure consists of divisions as shown in the following image A brief introduction of these divisions is given below Sections are the logical subdivision of program logic. A section is a collection of paragraphs. Paragraphs are the subdivision of a section or division. It is either a user defined or a predefined name followed by a period, and consists of zero or more sentencesentries. Sentences are the combination of one or more statements. Sentences appear only in the Procedure division. A sentence must end with a period. COBOL DB2 Program Introduction. Mainframes 3. 60. First, you need to declare the Cursor Query. DECLARE C1 CURSOR FOR is the statement used to declare a cursor. I am going to declare a cursor, which can retrieve Employee id, name, salary and joining date from the Employee table. You also need to supply the SQLCACOBOL Variable, that shall hold the results of the OPEN, FETCH and CLOSE Cursor operations. You want to be sure, that OPEN, FETCH and CLOSE Cursor operations go clean, without any errors, so you need SQLCA to check on that. You generally type an INCLUDE SQLCA entry. Now, you begin type executable COBOL Instructions in the PROCEDURE DIVISION. Essentially, the task of fetching data rows from the DB2 Table can be divided into 3 paragraphs 1. OPENing the Cursor 2. FETCHing data from the Cursor row by row and 3. CLOSEing Cursor. I have typed the MAIN Paragraph in the PROCEDURE DIVISION like this   Line 3. Open paragraph, to open the cursor. When you do a FETCH in SQL, it returnsretrieves back the row, the cursor is currently pointing to. Every time you FETCH, the current row is returned, and the cursor is incrementedset to the next row. A SQLCODE0 signals a successful FETCH. This sequential row after row process of FETCHing, continues on and on. But, how do you know, how many rows you want to fetch 5, 1. You dont The situation where the cursor points to the Last row, and there is no more data to get, is detected using the special SQLCODE1. A SQLCODE1. 00 is the special, exceptional condition, where the cursor points to the last row, and there are no more data rows to FETCH. You should do as many FETCHs until, you hit SQLCODE1. Line 3. 8 in the PROCEDURE DIVISION, performs FETCH paragraph to get one row at a time, repeatedly until SQLCODE is set to 1. Line 3. 9 performs the Close, to close the cursor. To Open a Cursorand execute the Cursor query, in SQL you type OPEN cursor name. I have coded 1. 00 OPEN Paragraph below, which executes the SQL instruction, OPEN EMPCSR on Line 4. When you OPEN EMPCSR, it means SELECT EMPID,ENAME,SALARY,JDATE FROM EMPLOYEE query will run. The results will be stored in a SQL Area EMPCSR. The contents pf the Cursor Area EMPCSR are 1    RAM    1. RAJ    2. 00. 0    2. RAKESH 3. 00. 0    2. A marker or a pointer is set to the first row in the Cursor Area. This pointer position, tells whats the next row to be read To fetchreceive data rows from the SQL Cursor area into the COBOL Program, in SQL you type FETCH cursor area name INTO  COBOL variables The 2. FETCH Paragraph from Lines 4. Cursor Area EMPCSR. So, this reads the row 1   RAM    1. But, when this data arrives in the COBOL Program, where is it stored So you also supply a list of COBOL Variables corresponding to each SQL Data value received. In the picture below, EMPLOYEE ID COBOL Variable will receive the value 1, EMPLOYEE NAME COBOL Variable will receive the value RAM,  EMPLOYEE SALARY COBOL Variable will receive the value 1. EMPLOYEE JDATE COBOL Variable will receive the value 2. FETCH cursor area name is a SQL Instruction. When you want to use COBOL Variablesnon SQL Variables like EMPLOYEE ID, EMPLOYEE NAME etc. SQL Instruction, you prefix them with a Colon. I have DISPLAYed the recently fetched EMPLOYEE INPUT RECORD. After the FETCH Operation is completed successfully, the SQLCODE is set to 0. The pointer is incremented and set to the next row in the cursor area. RAM    1. 00. 0    2. RAJ    2. 00. 0    2. RAKESH 3. 00. 0    2. The 2. 00 FETCH Paragraph is performed over and over again, till youve read the last row, until SQLCODE1. The 2nd FETCH will store 2 in EMPLOYEE ID, RAJ in EMPLOYEE NAME, 2. EMPLOYEE SALARY and 2.