Databases Reference
In-Depth Information
FIGURE B.48
Spiral approach.
In the spiral development approach, the requirements of the system are fluid. When the spiral
development commences, there is usually not a static, complete set of requirements for the develop-
ment of the system.
The third development approach is the “city” approach. In the city development approach devel-
opment is pretty much an ongoing thing. Like a city that is never complete, some development efforts
are ongoing things and are never complete.
Figure B.49
shows the city approach to development.
Tto understand the city approach to development, contrast the building of a city versus the build-
ing of a house. A house is reasonably finite. The house can either be lived in or cannot be lived in.
Relatively speaking, a house takes a short amount of time to build. Once built it is not normal for
major new renditions of the same house to be built. Most houses look pretty much the same 20 years
after they were completed.
A city on the other hand is undergoing continuous development. Consider Rome, Italy. Rome was
first occupied thousands of years ago, yet people are still building Rome today. While parts of Rome
are recognizable over the years, other parts of Rome are hardly the same. Major changes are made to
Rome. When Rome was first built there were no parking spaces or airports, but there are now.
There is then a very different approach to the building of a city versus the building of a house. The
healthcare information factory is much more like a city than a house, when it comes to the general
approach to construction.
The different styles of development are found in different places in the healthcare information fac-
tory.
Figure B.50
shows the different types of development and where they fit in the healthcare infor-
mation factory architecture.
Figure B.50
shows the individual providers use the SDLC when building their systems at the
local provider level. The spiral development approach is used to build the data warehouse at the local
