02
Sat, Nov
2 New Articles
  1. You are here:  
  2. Home
  3. Programming
  4. RPG
  5. Embedded SQL Operations Using Free Format

Embedded SQL Operations Using Free Format

RPG
Typography
  • Smaller Small Medium Big Bigger
  • Default Helvetica Segoe Georgia Times

Embedded Structured Query Language (SQL) has been available to the RPG programmer for a long time.

Editor's Note: This article is excerpted from chapter 7 of Free-Format RPG IV: Third Edition, by Jim Martin.

This chapter is intended to show you the differences between fixed-format RPG IV with embedded SQL and embedded SQL within a free-format RPG IV program. My assumption is that you already know how to code SQL statements. Only the differences between fixed- and free-format embedded SQL will be presented.

Database and Embedded SQL

SQL allows a user a great deal of flexibility when working with a database. A user can affect a large number of records within a file with very little code. The strengths of a procedural language such as RPG IV are combined with the strengths of SQL when embedding SQL statements within a program.

Fixed-Format Method

RPG source programs that contain embedded SQL have a member type of

SQLRPGLE rather than RPGLE. This member type causes the SQL precompiler

to be invoked. The precompiler modifies the /Exec SQL statements (mostly into API calls) prior to invoking the regular RPG IV compiler. The general rules to follow in fixed-format RPG IV are as follows:

  • An SQL statement must be preceded by the precompiler directive C/Exec SQL
  • The SQL statement must be followed by another precompiler directive, C/End-SQL.
  • The SQL statement can begin on the same line as the C/Exec SQL line, but most programmers code the SQL statement on a separate line.
  • Access to host variables is accomplished by preceding the variable name with a colon (:).
  • The SQL communications area is included in every program (in a data structure) in definition specifications.
  • Each source line of the SQL statement between the C/Exec SQL line and the C/End-SQL line must contain C+ in positions 6 and 7.
  • The SQL statement can be entered anywhere in positions 9–80. Position 8 must be left blank.

Listing 7-1 shows an example of an SQL statement in fixed-format RPG IV.

Embedded SQL Operations Using Free Format - Figure 1

Listing 7-1: Sample embedded SQL statement in fixed-format RPG IV

A nice feature of fixed format is the ability to prompt (using F4) and fill in values on the prompt screen.

Free-Format Method

While free format introduces some differences from fixed-format SQL, some things stay the same:

  • The source member type is still SQLRPGLE.
  • The SQL communications area (data structure) is included in every program, as before, in definition specifications.
  • Access to host variables is also the same, achieved by preceding the variable name with a colon (:).

The following points detail the changes to embedded SQL when you are coding within a free-format section of RPG IV code:

  • No C is placed in position
  • The SQL precompiler directive includes no preceding forward slash (/). The statement is just 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 to indicate that the literal is continued on the next line.
  • The SQL statement may be entered anywhere in positions 8–80, the same as any free-format statement.
  • The embedded SQL statement is ended with a semicolon (;), the same as other free-format statements. This character replaces the End-SQL statement that fixed format uses.
  • Prompting is not

Listing 7-2 shows an example of an embedded SQL statement coded in free-format RPG IV. It is the same statement that was used in Listing 7-1. The indenting in this example is done manually to aid the program reader. Multiple lines are used for the same reason, and to make it easier to make changes.

Embedded SQL Operations Using Free Format - Figure 2

Listing 7-2: Sample embedded SQL statement in free-format RPG IV

More of Jim's Free-Format RPG IV is coming soon in an upcoming MC Press Publication. Can't wait?  You can pick up Jim Martin's book, Free-Format RPG IV: Third Edition at the MC Press Bookstore Today!

JIM MARTIN

Jim Martin holds a BS degree in mathematics and an MS in computer science. For 26 years, he was employed by IBM, where he wrote RPG applications for customers and worked in the programming laboratory as a programmer on portions of CPF and the OS/400 operating system. After leaving IBM, Jim took post-graduate work in computer science and performed RPG training. He is an IBM-certified RPG IV developer and author of multiple bestselling editions of Free-Format RPG IV, which, since the book's initial publication in 2005, have taught thousands of RPG IV programmers how to be successful with the free-format coding style.

MC Press books written by Jim Martin available now on the MC Press Bookstore.

Free-Format RPG IV: Third Edition Free-Format RPG IV: Third Edition
Improve productivity, readability, and program maintenance with the free-format style of programming in RPG IV.
List Price $59.95

Now On Sale

Free-Format RPG IV: Second Edition Free-Format RPG IV: Second Edition
>Make the transition from coding in fixed-format RPG to free format.
List Price $59.95

Now On Sale
Functions in Free-Format RPG IV Functions in Free-Format RPG IV
Here’s the ultimate guide to writing RPG IV programs with functions in the free-format style.
List Price $59.95

Now On Sale
BLOG COMMENTS POWERED BY DISQUS

LATEST COMMENTS

Support MC Press Online

$

Book Reviews

Resource Center

  • SB Profound WC 5536 Have you been wondering about Node.js? Our free Node.js Webinar Series takes you from total beginner to creating a fully-functional IBM i Node.js business application. You can find Part 1 here. In Part 2 of our free Node.js Webinar Series, Brian May teaches you the different tooling options available for writing code, debugging, and using Git for version control. Brian will briefly discuss the different tools available, and demonstrate his preferred setup for Node development on IBM i or any platform. Attend this webinar to learn:

  • SB Profound WP 5539More than ever, there is a demand for IT to deliver innovation. Your IBM i has been an essential part of your business operations for years. However, your organization may struggle to maintain the current system and implement new projects. The thousands of customers we've worked with and surveyed state that expectations regarding the digital footprint and vision of the company are not aligned with the current IT environment.

  • SB HelpSystems ROBOT Generic IBM announced the E1080 servers using the latest Power10 processor in September 2021. The most powerful processor from IBM to date, Power10 is designed to handle the demands of doing business in today’s high-tech atmosphere, including running cloud applications, supporting big data, and managing AI workloads. But what does Power10 mean for your data center? In this recorded webinar, IBMers Dan Sundt and Dylan Boday join IBM Power Champion Tom Huntington for a discussion on why Power10 technology is the right strategic investment if you run IBM i, AIX, or Linux. In this action-packed hour, Tom will share trends from the IBM i and AIX user communities while Dan and Dylan dive into the tech specs for key hardware, including:

  • Magic MarkTRY the one package that solves all your document design and printing challenges on all your platforms. Produce bar code labels, electronic forms, ad hoc reports, and RFID tags – without programming! MarkMagic is the only document design and print solution that combines report writing, WYSIWYG label and forms design, and conditional printing in one integrated product. Make sure your data survives when catastrophe hits. Request your trial now!  Request Now.

  • SB HelpSystems ROBOT GenericForms of ransomware has been around for over 30 years, and with more and more organizations suffering attacks each year, it continues to endure. What has made ransomware such a durable threat and what is the best way to combat it? In order to prevent ransomware, organizations must first understand how it works.

  • SB HelpSystems ROBOT GenericIT security is a top priority for businesses around the world, but most IBM i pros don’t know where to begin—and most cybersecurity experts don’t know IBM i. In this session, Robin Tatam explores the business impact of lax IBM i security, the top vulnerabilities putting IBM i at risk, and the steps you can take to protect your organization. If you’re looking to avoid unexpected downtime or corrupted data, you don’t want to miss this session.

  • SB HelpSystems ROBOT GenericCan you trust all of your users all of the time? A typical end user receives 16 malicious emails each month, but only 17 percent of these phishing campaigns are reported to IT. Once an attack is underway, most organizations won’t discover the breach until six months later. A staggering amount of damage can occur in that time. Despite these risks, 93 percent of organizations are leaving their IBM i systems vulnerable to cybercrime. In this on-demand webinar, IBM i security experts Robin Tatam and Sandi Moore will reveal:

  • FORTRA Disaster protection is vital to every business. Yet, it often consists of patched together procedures that are prone to error. From automatic backups to data encryption to media management, Robot automates the routine (yet often complex) tasks of iSeries backup and recovery, saving you time and money and making the process safer and more reliable. Automate your backups with the Robot Backup and Recovery Solution. Key features include:

  • FORTRAManaging messages on your IBM i can be more than a full-time job if you have to do it manually. Messages need a response and resources must be monitored—often over multiple systems and across platforms. How can you be sure you won’t miss important system events? Automate your message center with the Robot Message Management Solution. Key features include:

  • FORTRAThe thought of printing, distributing, and storing iSeries reports manually may reduce you to tears. Paper and labor costs associated with report generation can spiral out of control. Mountains of paper threaten to swamp your files. Robot automates report bursting, distribution, bundling, and archiving, and offers secure, selective online report viewing. Manage your reports with the Robot Report Management Solution. Key features include:

  • FORTRAFor over 30 years, Robot has been a leader in systems management for IBM i. With batch job creation and scheduling at its core, the Robot Job Scheduling Solution reduces the opportunity for human error and helps you maintain service levels, automating even the biggest, most complex runbooks. Manage your job schedule with the Robot Job Scheduling Solution. Key features include:

  • LANSA Business users want new applications now. Market and regulatory pressures require faster application updates and delivery into production. Your IBM i developers may be approaching retirement, and you see no sure way to fill their positions with experienced developers. In addition, you may be caught between maintaining your existing applications and the uncertainty of moving to something new.

  • LANSAWhen it comes to creating your business applications, there are hundreds of coding platforms and programming languages to choose from. These options range from very complex traditional programming languages to Low-Code platforms where sometimes no traditional coding experience is needed. Download our whitepaper, The Power of Writing Code in a Low-Code Solution, and:

  • LANSASupply Chain is becoming increasingly complex and unpredictable. From raw materials for manufacturing to food supply chains, the journey from source to production to delivery to consumers is marred with inefficiencies, manual processes, shortages, recalls, counterfeits, and scandals. In this webinar, we discuss how:

  • The MC Resource Centers bring you the widest selection of white papers, trial software, and on-demand webcasts for you to choose from. >> Review the list of White Papers, Trial Software or On-Demand Webcast at the MC Press Resource Center. >> Add the items to yru Cart and complet he checkout process and submit

  • Profound Logic Have you been wondering about Node.js? Our free Node.js Webinar Series takes you from total beginner to creating a fully-functional IBM i Node.js business application.

  • SB Profound WC 5536Join us for this hour-long webcast that will explore:

  • Fortra IT managers hoping to find new IBM i talent are discovering that the pool of experienced RPG programmers and operators or administrators with intimate knowledge of the operating system and the applications that run on it is small. This begs the question: How will you manage the platform that supports such a big part of your business? This guide offers strategies and software suggestions to help you plan IT staffing and resources and smooth the transition after your AS/400 talent retires. Read on to learn: