Increasing agility with NoSQL - Making Sense of NoSQL - page 205

you've entered in the form into a single XML document. Most save operations into
a native XML database can be done with a single line of code, even if your form is
complex.
The real strength of XRX emerges when you need to modify your application. Add-
ing a new field can be done by adding a new element to the model and a few lines of
code to the view elements. That's it! No need to change the database, no recompila-
tion of middle-tier objects, and no need to write additional JavaScript code within the
browser. XRX keeps things simple.

9.4.3 Understanding the impact of XRX on agility

Today, we live in a world where many information technology departments aren't
focused on making it easy for business users to build and maintain their own applica-
tions. Yet this is exactly what XRX does. Form developers are no longer constrained by
IT development schedules of overworked staff who don't have time to learn the com-
plex business rules of each department. With some training, many users can maintain
and update their own forms applications.
XRX is a great example of how simplicity and standards drive agility. The fewer
components, the easier it is to build new and change existing forms. Because stan-
dards are reused, your team doesn't have to learn a new JavaScript library or a new
data format. XRX and NoSQL can have a transformative impact on the way work is
divided in a project. It means that information technology staff can focus on other
tasks rather than updating business rules in Java and JavaScript every time there's a
change request.
The lessons you've learned with XRX can be applied to other areas as well. If you
have a JSON document store like MongoDB, Couchbase, or CouchDB, you can build
JSON services to populate XForms models. There are even versions of XForms that
load and save JSON documents. The important architecture element is the elimina-
tion of the object-relational layer and the ability to avoid JavaScript programs on the
client. If you do this, then your SME s can take a more active role in your projects and
increase organizational agility.

9.5 Summary

The primary business driver behind the NoSQL movement was the need for graceful
horizontal scalability. This forced a break from the past, and opened new doors to
innovative ways of storing data. It allowed innovators to build mature systems that
facilitate agile software development. The phrase “ We came for the scalability—we stayed
for the agility ” is an excellent summary of this process.
In this chapter, we stressed that comparing agility of two database architecture
alternatives is difficult, because overall agility is buried in the software developer's
stack. Despite the challenges, we feel it's worthwhile to create use-case-driven thought
experiments to help guide objective evaluations.