Categories: 01a - RPG (EN)

Alternative to OVRDBF in F specifications (dcl-f free)

It is not new to RPG but every now and then it is useful to remember that if we want to use, within our RPG programs, some fancy file names that “point” to a different file (for example when we have the same file open in INPUT and in UPDATE-ADD with two different names), we can use the EXTFILE and EXTDESC keywords and avoid OVRDBFs in the CL or at compile time.

Let’s take this example from John B in Midrange.com discussions: https://archive.midrange.com/rpg400-l/202208/msg00115.html

- >> EXTFILE eliminates the need to do a RUN-TIME OVRDBF.
--- >> EXTDESC eliminates the need of a COMPILE-TIME OVRDBF.

       dcl-f bar542d workstn infds (ScrDS) extfile ('GLOBAL / BAR542D') extdesc ('GLOBAL / BAR542D');

Simon Hutchinson already told us about it in 2013: Useful keywords for your F-specs

Related Posts
DB2 for i SQL – String Manipulation – POSSTR-LOCATE-LOCATE_IN_STRING (EN)

Introduction Often, in our applications, we need to work with text strings, and DB2 SQL can come in very useful Read more

DB2 for i – FAQ & Howtos (EN)

DB2 Database and SQL ... maybe the most important things on IBM i platform: here's a collection of FAQs, tips Read more

IBM i 7.4 Announcement (En)

Comes directly with the Easter egg this IBM announcement for the news of the IBM i 7.4 version, iNext version Read more

Generated Always Columns (EN)

Introduction "Generated Always Column": are columns, table fields, filled by DB2 engine: something like columns with a default value but Read more

--- Roberto De Pedrini Faq400.com

View Comments

  • Even simpler is to use extfile(*ExtDesc). Eg.
    dcl-f bar542d workstn infds(ScrDS)
    extdesc('GLOBAL/BAR542D')
    extfile(*ExtDesc);

Recent Posts

VsCode Extention: Bob Cozzi’s RPG IV to RPG Free Conversion

👉 Review: Bob Cozzi’s RPG IV to RPG Free Conversion – a useful VS Code extension for RPG modernization If…

3 months ago

IBM i & SQL Tips #010 – Locating Programs in the Call Stack with STACK_INFO

Hello everyone, I’d like to highlight another excellent contribution by Massimo Duca, part of his ongoing IBM i & SQL…

3 months ago

Trying out “Display File DDS Edit” for VS Code

Intrigued by some recent posts from Cristian Larsen on LinkedIn (New Release – Display File DDS Edit v 0.10.1), I…

3 months ago

Project Bob: the next-gen AI partner for IBM i and IBM Z application development

Hello everyone, Today I’d like to draw your attention to a major new announcement from IBM: Project Bob — a…

3 months ago

IBM i & SQL Tips #6: Calling REST APIs and Parsing JSON Responses with SQL

I want to share with you a particularly useful article by Massimo Duca in the IBM i & SQL Tips…

4 months ago

How Parameter Passing Works in IBM i Programs (RPG / Cobol)

Hello everyone, I’d like to highlight a very useful article by Marco Riva on Markonetools, where he clearly explains how…

4 months ago