Tue, Dec
5 New Articles

TechTip: Using the DB2 Programming Language (PL), Part 1

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


Everybody’s talking about data-centric programming. Well, I mean you won’t hear people talking about it in a bar or anywhere fun, but whatever. But this isn’t a bar, is it? No, more’s the pity. So, since there’s nothing else to do, let’s talk.

Written by David Shirey  

A few months ago, I wrote an article about data-centric programming. And it was very nice and all, but I want to get specific and cover a fair amount of detail about how to actually go about it.

What Is Data-Centric Programming?

I think the first thing we should do is remind ourselves just what data-centric programming is. In short, it means using a database-based language to do your work instead of a more standard procedural language like RPG.

In order to be useful, this data-centric language must consist of not only the data access and update procedures that we are used to with embedded SQL, but also conditional, looping, and other control-type statements required by a “real” language. If it does, then it can really and truly compete with RPG.

Many data-centric languages are out there, but for the i world, that would be the Programming Language (PL) that is part of DB2.

Why Bother?

I guess the first question we need to answer, or at least review from the previous article, is why you want to bother.

After all, we have RPG, and we can do everything we need in there. And if you want to use DB2 instead of the DDS files, you can do that with embedded SQL in your RPG program.

I suppose there are a bunch of reasons, but the only one that really stands out to me is you would do this because you want to free yourself (and your applications) from a language that struggles mightily not to look archaic. By abandoning RPG in favor of a data-centric language, you are eliminating the need to find RPG programmers and removing the specter of languages past from your system. DB2/SQL is a “modern” language the way everyone views things, and it is something that almost all new programmers understand. I have to admit, I have problems with this because I am an RPG guy and especially an RPG free-format guy, but SQL is everywhere, and if I need new talent, I don’t have to look for someone who knows RPG, just someone who knows SQL.

What Is PL?

As I said above, the language we will look at is the DB2 Programming Language (PL), and it comes standard on your i as part of DB2. Yeah, something you don’t have to buy!

It is based in the same SQL that we could embed in RPG, but it goes further and special functions have been added that allow it to do decision-making, iterations, and other activities that separate a fully functional language from the mere data access and update capabilities of SQL.

The one caveat is that PL has no capability to display data the way RPG does, although most people aren’t interested in showing data the way RPG does anymore. In both cases, you would involve some other language to do the web display of the data accessed and manipulated.

Bottom line: DB2 PL is a viable alternative to traditional RPG and may be something you want to investigate more. To do so, we are going to spend some time figuring out how it works and how to get it off the ground.

What Does It Look Like?

I know that, when I am looking at a new language, the first thing I want to know is what it “looks like.” Not what it can do or even how finicky it is, but what it looks like. With languages, as with people, we draw certain conclusions right off the bat based on looks. Is it structured in any way, can it be read like English, does its syntax look “normal” to me?

Since it’s origins are DB2, it looks a lot like SQL. That is, we have the standard SQL-type commands: Insert, Fetch, etc. But there are also other commands too because, for it to be a functioning language, we need to be able to do control statements (IF-THEN, WHEN), loops (LOOP, FOR, WHILE, REPEAT), and basic set-equal-to logic (SET). But all that shall be revealed in its proper time.  

Where to Store Them

So how do you get started with PL? Well, the first element is to figure out how you are going to set up the scripts. We are used to a world where all programs belong to some source file (QRPGLESRC, QCLSRC, etc.) in the i.

There is no preset source file where your PL scripts will reside, so you have to create one with the CRTSRCF command.

What you name it is up to you. I set mine up as QPLSRC. That bothers me in a way because I like to have three characters after the Q and before the SRC, but sometimes you have to just deal with things. At least I can tell that these are PL scripts. Of course, you could just dump them into any existing source file, but that is way too untidy for me.

What is important is that, when you create the scripts, you create them with a source type of SQL. And don’t think you can use RPGSQL or RPGSQLLE as the type. Those are for RPG programs with embedded SQL, and that is not what we are doing.

That’s All, Folks

And I am afraid that is all for this month. In our next tip, we will actually create a working PL script, compile it, and run the dang thing. Can’t wait. See you then.

David Shirey

David Shirey is president of Shirey Consulting Services, providing technical and business consulting services for the IBM i world. Among the services provided are IBM i technical support, including application design and programming services, ERP installation and support, and EDI setup and maintenance. With experience in a wide range of industries (food and beverage to electronics to hard manufacturing to drugs--the legal kind--to medical devices to fulfillment houses) and a wide range of business sizes served (from very large, like Fresh Express, to much smaller, like Labconco), SCS has the knowledge and experience to assist with your technical or business issues. You may contact Dave by email at This email address is being protected from spambots. You need JavaScript enabled to view it. or by phone at (616) 304-2466.

MC Press books written by David Shirey available now on the MC Press Bookstore.

21st Century RPG: /Free, ILE, and MVC 21st Century RPG: /Free, ILE, and MVC
Boost your productivity, modernize your applications, and upgrade your skills with these powerful coding methods.
List Price $69.95

Now On Sale



Support MC Press Online

$0.00 Raised:

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: