What is a subfile? An overview of AS400 iSeries and IBM i display file subfiles.

An IBM i subfile has the same setup as previous generations of AS/400 and iSeries. A subfile is a powerful feature that allows you to display and manage multiple records on a single screen. Let me break it down for you:

Purpose of Subfiles:
Subfiles are used to present a list of values or records to the user.
They allow you to handle multiple records of the same type on a display screen.
You can perform actions like scrolling through the list, selecting items, and making changes.
How Subfiles Work:
A subfile is defined in a display file (DSPF).
The records displayed in the subfile are read from a database file through a program.
The program writes the records to the device file, which is then displayed on the subfile screen.
Types of Subfiles:
Load All Subfile: Loads the entire subfile at once. Suitable for smaller datasets.
Page at a Time Subfile: Loads one page of records at a time. More efficient for larger datasets.
Expanding Page Subfile: Loads one page of records at a time, expanding as it adds pages.

[RickyThompson]

One I would love to see is a one page at a time subfile that is all written in SQL that has pageup/page down and position to and also allows to select edit/delete from multiple pages. I've written a skeleton one that I use but it has it's own quirks. I basically save all the select options to a data structure along with a key so that I can reload and save the selection options. But I would like to see others techniques but this might not be something anyone else is interested in. Just looking for best practices.

[edwardooom]

HI Nick, have you continued this video where you compile the code and walk through this to help us understand, if so do you have a link for the course on your website, thank you