Now we begin to understand how long information will need
to be held and to be available in our computerised system.
This indicates where the forms (if that’s what they are) are
stored at the moment, and thus the location from which they
will have to be obtained for data creation.
Volumes: Here we can record the number of new documents per month,
per year or whatever, and what the overall growth in numbers
is. This, clearly, is of some importance in working out how
much space must be reserved in the system for the data.
Apart from the people who record the information initially, we
are also interested in who needs to access it and for what
reason. Again this will inﬂuence the access privileges we
deﬁne for the computer system.
Finally, for each data item on the form, we record its name,
its format and description, whether there are deﬁned ranges
within which the values must ﬁt, and where the data comes
from. This is extremely useful in modelling the data for the
proposed system (for details of which, see Techniques 63 and
64, entity relationship modelling and class modelling), and,
again, in sizing the proposed system.
Using document analysis
Some commonsense has to be used in the selection of data sources to be
documented in this way. We do not necessarily need to examine every form,
screen or report currently used. Instead we need to select those that will give us
the best overall picture of the proposed system’s data requirements.
Some BAs may feel that such detailed work on data is not really part of their job,
leaving this to the systems analysts or even the developers. However, it must be
remembered that the BA probably has the closest contact with the system’s
proposed users and is therefore in the best position to search out the relevant
DOCUMENTING THE RESULTS
Technique 20: Rich pictures
Description of the technique
Rich pictures were popularised in the soft systems methodology, put forward by
Professor Peter Checkland and his associates in the 1980s (Checkland 1993).
The idea is to capture in pictorial form the essential elements of a business issue
or problem, to facilitate a more holistic understanding and analysis of it. There
are no rules as to what may or could be captured in a rich picture, nor about what
symbols should be used, so it is a very free-format technique indeed. Typically,
though, the sorts of things we want to represent in a rich picture include: