Acknowledgment: As always a huge thank you to Bruce Robertson, for inventing virtual list, and for many other contributions to the FM community over the years.
Introduction
As a follow up to my recent “Virtual List on Steroids” presentations at DIG-FM and dotFMP, today I want to take a fresh look at using JSON arrays in conjunction with Virtual List Reporting.
JSON arrays + Virtual List are a natural fit, but, as we shall see, small changes in methodology can make a huge difference in terms of performance, and the approaches we’re going to explore today are the result of a lot of trial and error, and incorporate feedback and suggestions from Dave Graham, Paul Jansen and Perren Smith.
What follows will assume the reader is somewhat familiar with the basic ideas behind Virtual List. If you aren’t familiar, or need a refresher, check out Virtual List Simplified. We’ll get to the demos in just a minute, but first, a review of some of the benefits of using virtual list.
- Flexible framework accommodates complex reporting challenges
- Fast performance
- No need to tamper with schema in your data tables or on the relationships graph
- Unlike traditional FM reports, you can easily combine data from unrelated tables
- Under certain circumstances, virtual list reports (VLRs) can be much faster to develop than traditional FM reports
- 100% multi-user safe and friendly
Overview
Here’s the main idea in a nutshell: