Complete AS/400 RPG Application: Input, Output, and Storage

Introduction

The AS/400 system (now IBM i) uses RPG (Report Program Generator) to build robust business applications. This guide covers a complete RPG application, including user input, data processing, and database storage.

Database Table (DB2)

First, create a DB2 table to store customer data.

    CREATE TABLE CUSTOMERS (
        ID INT PRIMARY KEY,
        NAME VARCHAR(50),
        BALANCE DECIMAL(10,2)
    );
    

Display File (User Input) - CUSTDSPF.DSPF

A DDS (Data Description Specifications) file for user input.

    A          R CUSTOMER
    A            CUSTID        5  0B  5  2
    A            CUSTNAME     20  B  7  2
    A            CUSTBAL     10  2B  9  2
    A            ENTERKEY      1  0B  11  2
    A          K  ENTERKEY
    

RPGLE Program (Processing and Storage) - CUSTRPG.RPGLE

This program interacts with the user, retrieves input, and updates the database.

    **Free
    DCLF CUSTDSPF;
    DCL-S CustomerName CHAR(20);
    DCL-S CustomerBalance PACKED(10:2);
    
    EXFMT CUSTOMER;  // Display input screen
    
    IF ENTERKEY = '1';
        EXEC SQL INSERT INTO CUSTOMERS (ID, NAME, BALANCE) VALUES (:CUSTID, :CUSTNAME, :CUSTBAL);
        DSPLY 'Record Saved Successfully';
    ENDIF;
    
    *INLR = *ON;
    

Retrieving and Displaying Stored Data

    **Free
    DCL-S CustName CHAR(20);
    DCL-S CustBalance PACKED(10:2);
    
    EXEC SQL SELECT NAME, BALANCE INTO :CustName, :CustBalance FROM CUSTOMERS WHERE ID = :CUSTID;
    
    DSPLY 'Customer Name: ' + CustName;
    DSPLY 'Customer Balance: ' + %CHAR(CustBalance);
    
    *INLR = *ON;
    

Conclusion

This complete RPG application allows users to input customer details, store them in DB2, and retrieve them later.