Understanding Embedded Sql In Free-Format Rpg Programming

Oct. 20, 2025, 3:04 p.m.

Tags: embedded rpg sql

The provided source material is insufficient to produce a 2000-word article about free samples, promotional offers, no-cost product trials, brand freebies, and mail-in sample programs. Below is a factual summary based on available data regarding embedded SQL in RPG programming.

Introduction

The provided source documents contain information about embedded Structured Query Language (SQL) within RPG programming, specifically focusing on the differences between fixed-format and free-format RPG IV when implementing SQL operations. These resources explain how SQL statements can be incorporated into RPG programs to enhance database operations, combining the procedural strengths of RPG with the data manipulation capabilities of SQL.

Free-Format RPG with Embedded SQL

Free-format RPG IV allows programmers to write code without the strict column positioning requirements of traditional fixed-format RPG. When embedding SQL in free-format RPG, several specific syntax differences must be observed compared to the fixed-format approach.

In fixed-format RPG IV, programs containing embedded SQL use a member type of SQLRPGLE rather than RPGLE. This member type invokes the SQL precompiler, which modifies the /Exec SQL statements (mostly into API calls) before the regular RPG IV compiler processes the code. The general rules for fixed-format embedded SQL include:

SQL statements must be preceded by the precompiler directive C/Exec SQL
SQL statements must be followed by another precompiler directive C/End-SQL
SQL statements can begin on the same line as C/Exec SQL or on a separate line

When coding within a free-format section of RPG IV, the approach differs significantly:

No C is placed in position
The SQL precompiler directive includes no preceding forward slash (/). The statement is simply Exec SQL.
No C+ is used on subsequent lines; continuation is automatic
If a character literal must be split between lines, include a "+" symbol at the end of the first line
SQL statements may be entered anywhere in positions 8-80, the same as any free-format statement
The embedded SQL statement is ended with a semicolon (;), replacing the End-SQL statement used in fixed format

Access to host variables remains the same in both formats, achieved by preceding the variable name with a colon (:).

Practical Implementation Examples

Several code examples demonstrate how embedded SQL works in free-format RPG. One example shows selecting all fields from a record and placing the contents into a data structure:

Exec SQL Select * Into :mainDS From MYLIB/MYFILE Where IDFIELD = :KEY_VALUE;

A more complex example includes declaring a cursor, preparing a statement, opening the cursor, fetching data, and closing the cursor:

Dcl-S sql Char(32000) Inz('Select * from mynames Order by USERNAME'); Exec SQL Declare mainCursor Cursor For mainStatement; Exec SQL Prepare mainStatement From :sql; Exec SQL Open mainCursor; Exec SQL Fetch Next From mainCursor Into :mainDS;

This example demonstrates how multiple SQL operations can be integrated within free-format RPG code, though the process requires careful attention to syntax and structure.

Challenges with Embedded SQL in Free-Format RPG

One significant challenge noted in the source material is what some programmers refer to as "the ugly factor" - the need to constantly drop in and out of /free to execute SQL statements. This approach can result in code that is difficult to read and manage, especially when multiple cursors, select statements, updates, deletes, and inserts are interspersed with sections of free-format code.

The complexity increases when dealing with multiple SQL operations, as the programmer must manage compiler directives alongside actual code. Some developers find this approach so problematic that they avoid using /free format altogether, despite its other advantages.

Complete SQLRPGLE Program Example

A complete example demonstrates an SQLRPGLE program that connects to a database, selects customers from a table, filters by city, and displays customer names:

``` *FREE ctl-opt dftactgrp(no) actgrp(*caller) sql; Dcl-S CustID Int(10); Dcl-S Name Varchar(50); Dcl-S City Varchar(50);

Exec SQL Set Option Commit = *None; Exec SQL Declare C1 Cursor For Select CustID, Name, City From Customers Where City = 'Paris' Order By Name; Exec SQL Open C1;

Dow 1 = 1; Exec SQL Fetch Next From C1 Into :CustID, :Name, :City; If SQLCODE = 100; Leave; // No more data ElseIf SQLCODE < 0; Dsply ('SQL Error: ' + %Char(SQLCODE)); Leave; EndIf; Dsply ('Customer: ' + %Trim(Name) + ' - ' + %Trim(City)); EndDo;

Exec SQL Close C1; *INLR = *ON; Return; ```

This example illustrates key concepts of embedded SQL RPG programming, including: - Embedded SQL statements directly in RPG code - Cursor usage to fetch multiple rows - Host variables (prefixed with colons) used in SQL statements - SQLCODE checking to verify operation results

Extended Functionality

The SQLRPGLE example can be extended to include additional database operations: - INSERT: Adding new records - UPDATE: Modifying existing records - DELETE: Removing records - Enhanced error handling with SQLSTATE and SQLCODE

These extensions demonstrate the versatility of embedded SQL within RPG programs for comprehensive database operations.

Conclusion

The provided source material focuses exclusively on technical aspects of embedded SQL in RPG programming, particularly the differences between fixed-format and free-format implementations. While this information is valuable for RPG developers working with database operations, it contains no relevant content regarding consumer free samples, promotional offers, or product trials as requested in the original task assignment.