Cobol accessing Mysql

COBOL & Mysql
cobol now easily accessing

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Now it became easy to access Mysql files from MicroFocus COBOL programs.
Just change a configuration, and your program will be able to access both, MF files, as well as tables in MYSQL, transparently to user and developer of the project.
Don’t need to alter your program, nor losing all investments made so far, it is fast and easy to migrate to database.
Quickly and easily, you can enjoy the benefits of databases, integrating your application with a multitude of new features that are becoming available all the time.
Forget about former limitations. No slavery any more.
From now on you can have part of your application developed in COBOL, and additional modules in Java, C #, Visual Basic, HTML, Ajax etc ... interacting and collaborating with your application in a natural and transparent way, making your product robust, versatile, safe, among many other advantages.
You, who might be considering migrating to another platform, and always faced the impossibility of having to re-develop every product before, and then to migrate, consider your troubles as solved.
With EXTMYSQL you just continue operating your system as before and, then, start slowly developing the new features on the new platform, replacing the old routines as much and as far as possible until the migration is complete.
Or if you want to enjoy the benefits of the database, and do not want or have the time to study and know the background of this new tool all the way, even so EXTMYSQL is also useful, because as your programs need not be changed, you will interact with the data bank using traditional commands READ, WRITE, REWRITE, DELETE, START, OPEN, CLOSE etc... exactly as you always did.

**************************************************************************
      *  IMEDIATA INFORMATICA EMPRESARIAL LTDA                                 *
      *  PROGRAMA - CnvMfMy - Converte arquivo gerado originalmente em COBOL   *
      *                       para Banco de dados Mysql                        *
      **************************************************************************
       IDENTIFICATION DIVISION.
       PROGRAM-ID.    CnvMfMy.
       AUTHOR.        Franco Stringari Pudler.
       ENVIRONMENT    DIVISION.
       CONFIGURATION  SECTION.
       SPECIAL-NAMES. DECIMAL-POINT IS COMMA.
       INPUT-OUTPUT   SECTION.
       FILE-CONTROL.

*> Informa que o arquivo é padrão MYSQL

SELECT ARQMYS ASSIGN TO DYNAMIC W-LABMSQ
                   ORGANIZATION IS INDEXED
                   ACCESS MODE  IS DYNAMIC
                   LOCK MODE    IS MANUAL
                   FILE STATUS  IS W-STATUS
                   RECORD KEY   IS MY-LAN
                   ALTERNATE RECORD KEY IS MY-CTA
                                WITH DUPLICATES.

*> Informa que próximo arquivo é padrão DEFAULT MF

SELECT ARQMFS ASSIGN TO DYNAMIC W-LABMFS
                   ORGANIZATION IS INDEXED
                   ACCESS MODE  IS DYNAMIC
                   LOCK MODE    IS MANUAL
                   FILE STATUS  IS W-STATUS
                   RECORD KEY   IS MF-LAN
                   ALTERNATE RECORD KEY IS MF-CTA
                                WITH DUPLICATES.

DATA DIVISION.
       FILE SECTION.

*> Definição do registro do arquivo que será gerado no MySql
       FD  ARQMYS.
       01  MY-REG.
           02 MY-SIT   PIC  X(01).
           02 MY-LAN   PIC S9(09)    COMP-3.
           02 MY-CTA   PIC S9(15)    COMP-3.
           02 MY-CDH   PIC S9(05)    COMP-3.
           02 MY-HST   PIC  X(30).
           02 MY-DTA   PIC S9(09)    COMP-3.
           02 MY-VAL   PIC S9(13)V99 COMP-3.

*> Definição do registro do arquivo com os dados originalmente gerados no padrão MF
       FD  ARQMFS.
       01  MF-REG.
           02 MF-SIT   PIC  X(01).
           02 MF-LAN   PIC S9(09)    COMP-3.
           02 MF-CTA   PIC S9(15)    COMP-3.
           02 MF-CDH   PIC S9(05)    COMP-3.
           02 MF-HST   PIC  X(30).
           02 MF-DTA   PIC S9(09)    COMP-3.
           02 MF-VAL   PIC S9(13)V99 COMP-3.

WORKING-STORAGE SECTION.
       77  W-LABMFS    PIC  X(60) VALUE "ARQMFS".
       77  W-LABMSQ    PIC  X(60) VALUE SPACES.
       77  W-STATUS    PIC  X(02).
       88  STAT-ERRO            VALUE X"3100" THRU X"3943"
                                      X"3945" THRU X"39EE".

88  DUPLICADO            VALUE "22".

77  W-MSG       PIC  X(80) VALUE SPACES.

LINKAGE SECTION.

PROCEDURE DIVISION.
       INICIO.

MOVE  "ARQMFS"    TO W-LABMFS.  *> Define onde estão os dados

OPEN INPUT ARQMFS.              *> Abre arquivo MF
           IF STAT-ERRO                    *> Verifica se abertura foi OK
              STRING  "Abrindo Lote[" W-LABMFS "] Status"
                     W-STATUS DELIMITED BY "  " INTO W-MSG
              DISPLAY W-MSG                *> Comunica causa do problema
              STOP RUN.

MOVE  "@127.0.0.1@3306@root@1234@imediata@ARQMYS"
                             TO W-LABMSQ.  *> Define parametros para o MySql

OPEN I-O ARQMYS.                *> Abre arquivo no MySql
           IF STAT-ERRO
              DISPLAY "Criando Arquivo de destino"
              STOP RUN.

MOVE  ZEROS       TO MF-LAN.    *> Define ponto de partida
           START ARQMFS KEY IS NOT LESS THAN MF-LAN.  *> Posiciona no registro Cf definido acima
           PERFORM UNTIL STAT-ERRO                    *> Loop para geração do arquivo
              READ ARQMFS NEXT RECORD                 *> Recupera registro no arquivo Micro Focus
                 AT END DISPLAY "Fim conversão sem problemas" *> Termino sem problemas
                 NOT AT END                           *> Encontrou registro
                    MOVE  MF-REG  TO MY-REG           *> Move estrutura MF para Mysql
                    WRITE MY-REG                      *> Grava registro na tabela Mysql
                    IF DUPLICADO                      *> Teste se registro já estava cadastrado
                       MOVE  ZEROS TO W-STATUS        *> Evita encerramento prematuro caso registro já exista
                    ELSE
                       IF STAT-ERRO
                          DISPLAY "Erro gerando registro no Mysql, Staus  *> Não conseguiu gerar o registro
      -                           "[" W-STATUS "]"    *> Retorna possível causa do erro
                          STOP RUN                    *> Encerra processo
                       END-IF
                    END-IF
              END-READ
           END-PERFORM.

CLOSE ARQMFS.       *> Fecha os arquivos
           CLOSE ARQMYS.

STOP RUN.

Download - Program source for performance testing, with more than 800,000 records.
We encourage you to make changes and new tests, but also demonstrates the use of additional resources as LIKE "%%" combined with COBOL.
File to be downloaded with 12,000 Kb.
You should compile with your COBOL, any questions, please contact us.
Unzip the downloaded file, run the MYSQL script, compile the source program DEMOCEP.CBL, and do all the tests you want to evaluate our proposal.
Do nothing without a backup of all content from your computer, or the guarantee of being able to return to the situation prior to any procedure to be adopted.
We are not responsible for any damage or injury which might occur by chance.

This feature was tested using Micro Focus Cobol Version 4.0.38, NetExpress 3.0 and 3.1, running on Windows, other versions on request and Mysql 5.1.
Presently it is already running on LINUX.

See also:
Micro Focus, Cobol manufacturer used.
Mysql, maker of the database used.

Known limitations:

Redefinition of fields in COBOL is treated in Mysql as a single field, in this case it is recommended to change the program.

START command on tables with many records, can become a slow.

Problem can be bypassed, using a routine that allows reversing the sequence of filtering.

Using COBOL, filtering of records is done immediately after the reading of the record, in SQL database, the filtering is done by the server, returning only the desired records, and thereby reducing the volume of data traveling on the network.

Added features that help overcome this deficiency : MontaWhere and IgualaCmp.
These two routines are documented on this site right below, and serve several other purposes, significantly expanding the resources available to the COBOL programmer.

READ NEXT, READ PREVIOUS followed without a START command between one sequence and another.
Though it works, because of the way Mysql treats its accesses, this practice reduces the speed of the application mainlyn bases with many records.

To circumvent and offset this limitation, a possibility was added to combine the use of resources of the database with the program in COBOL.
This can be implemented in an extremely simple and easy way by allowing access of commands type LIKE "%%" of the database.

For further information please contact us by email pudler@mercosoft.com.br referring to subject "COBOL & MYSQL"
or by phone: 5551 96031151

Franco Stringari Pudler, email franco@imediata.com.br