Sat, Jul
2 New Articles

TechTip: SQL GetMiles Function

  • Smaller Small Medium Big Bigger
  • Default Helvetica Segoe Georgia Times
SQL functions allow you to use complex calculations to define field values. A good example is the calculation used to determine the distance between two ZIP codes. This type of function can be extremely useful within Web-based applications for calculating freight costs or for displaying store locations closest to a defined ZIP code. This tip describes how to create an SQL function that you can use to determine the distance between two ZIP codes and how to use this function within applications.

ZIP It Up!

Before you can start examining the function that determines distance between two ZIP codes, you need to examine the data required. Included with the code for this article is zipfile.savf, a physical file containing five-digit United States ZIP codes, along with their associated state abbreviations and longitude and latitude values. This data is from the 2000 U.S. Census Bureau census. The DDS source for this file is in Figure 1.

A* ZIP CODE MASTER FILE                                           
A*                       SRCFILE(QDDSSRC)                         
A          R ZIPS                                                 
A            ZIPCD          5          TEXT('5 DIGIT ZIP')        
A            STAB           2          TEXT('STATE ABBREV')       
A            LONG          15  5       TEXT('LONGITUDE')          
A            LAT           15  5       TEXT('LATITUDE')           
A          K ZIPCD                                                
A          K LONG                                                 
A          K LAT                                                  

Figure 1: This is the DDS source for the ZipCodes physical file.

To load this file on your iSeries, you must first create the save file in QGPL using the following command:


Once you've created the save file, you're ready to load the save file data into this file using FTP, as shown in Figure 2.

ftp> open
Connected to
220-QTCP at
220 Connection will close if idle more than 15 minutes.
User ( userid
331 Enter password.
230 USERID logged on.
ftp> cd QGPL
250 "QGPL" is current library.
ftp> bin
200 Representation type is binary IMAGE.
ftp> put zipdata.savf zipssavf
200 PORT subcommand request successful.
150 Sending file to member ZIPSSAVF in file ZIPSSAVF in library QGPL.
250 File transfer completed successfully.
ftp: 3020160 bytes sent in 3.56Seconds 847.65Kbytes/sec.
ftp> quit                         

Figure 2: Load the ZIP code data file onto the iSeries using FTP.

Within this example, replace the IP address shown ( with the IP address of your iSeries.

Next, you'll have to restore the physical file with the RSTOBJ command:


Building the Function

Now that you have the ZIP code data loaded into your iSeries, you're ready to take a look at the SQL function that you'll use with this data. This function calculates the number of air miles, nautical miles, or kilometers between ZIP codes, using the longitude and latitude points associated with each ZIP code. The source for the GetMiles function is shown in Figure 3.

      DECLARE @PI FLOAT;      
      DECLARE @X FLOAT;        
      DECLARE @LAT1 FLOAT;           
      DECLARE @LONG1 FLOAT;        
      SELECT LAT, "LONG" INTO @LAT2, @LONG2         
      SET @PI=3.1415927;        
      SET @X = (SIN((@LAT1 * @PI/180)) * SIN((@LAT2* @PI/180)) 
               + COS((@LAT1* @PI/180)) * COS((@LAT2* @PI/180)) 
               * COS(ABS(((@LONG2* @PI/180))-((@LONG1*@PI/180))
      SET @X = ATAN((SQRT(1-(@X*@X)))/@X);   
      SET @DISTANCE = (1.852 * 60.0 * ((@X/@PI)*180));  
      IF (UPPER(@UNIT)='M') THEN       
           SET @DISTANCE = (@DISTANCE * .621371192);       
           IF (UPPER(@UNIT)='N') THEN 
                SET @DISTANCE = (@DISTANCE * 0.539956803);     
           END IF;               
      END IF;         
      RETURN @DISTANCE;     

Figure 3: Use this source to create the GetMiles function.
To create this function, copy the source in Figure 3 into a source physical file (QSQLSRC, for example). Next, use the RUNSQLSTM command:


The formula contained within the GetMiles function uses the circumference of the Earth along with the longitude and latitude values that correspond to each ZIP code supplied. The function accepts three parameters: the five-character origin ZIP, the five-character destination ZIP, and the one-character unit of measure value representing the value to be returned. The value calculated is represented as kilometers by default but is converted to either air miles or nautical miles, based on the third parameter. Use a value of 'M' for air miles or a value of 'N' for nautical miles. Any other value specified will return the resulting distance in kilometers.

Once the function has been created, you can test it using the Interactive SQL console by typing the command STRSQL. From the console, type this SELECT statement:

SELECT QGPL.GETMILES('18222', '90210', 'M')

When executed, this statement will return multiple rows showing the air miles distance between these two ZIP codes. In this example, the file specified on the FROM clause is used for example purposes only.

Putting the Function to Use

Once you've successfully built and tested the GetMiles function, you're ready to put it to practical use. The example shown below calculates a shipping charge based on the origin ZIP (ORGZIP) and destination ZIP (DSTZIP) fields from the ORDERS file and joins to the CARRIERS file to get the rate per mile (RTPRMI) value.


A slightly more complicated example uses the function as part of an ORDER BY clause to return the data based on distance in miles. The statement for this example is shown below.


This is an example of how you would use the function to display locations closest to a defined location. For instance, you could use it to create Web pages that allow a user to display stores closest to their home (the specified origin ZIP). To achieve that, you would replace the origin ZIP in the example with the value of the variable containing the user's origin ZIP.

This example shows how you can take an otherwise difficult task and make it a simple part of an SQL statement. This function has oodles of uses, a few of which we've examined here, but many more of which you'll discover on your own now that you've got GetMiles.

Mike Faust is MIS Manager for The Lehigh Group in Macungie, Pennsylvania. Mike is also the author of the books The iSeries and AS/400 Programmer's Guide to Cool Things and Active Server Pages Primer from MC Press. You can contact Mike at This email address is being protected from spambots. You need JavaScript enabled to view it..

Mike Faust

Mike Faust is a senior consultant/analyst for Retail Technologies Corporation in Orlando, Florida. Mike is also the author of the books Active Server Pages Primer, The iSeries and AS/400 Programmer's Guide to Cool Things, JavaScript for the Business Developer, and SQL Built-in Functions and Stored Procedures. You can contact Mike at This email address is being protected from spambots. You need JavaScript enabled to view it..

MC Press books written by Mike Faust available now on the MC Press Bookstore.

Active Server Pages Primer Active Server Pages Primer
Learn how to make the most of ASP while creating a fully functional ASP "shopping cart" application.
List Price $79.00

Now On Sale

JavaScript for the Business Developer JavaScript for the Business Developer
Learn how JavaScript can help you create dynamic business applications with Web browser interfaces.
List Price $44.95

Now On Sale

SQL Built-in Functions and Stored Procedures SQL Built-in Functions and Stored Procedures
Unleash the full power of SQL with these highly useful tools.
List Price $49.95

Now On Sale



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: