Information analysis & data modelling

Before a building is constructed, detailed analysis is required to ensure that the building is what is required.

This includes,

Gathering information from the future owner, regarding the purpose of the structure.
Producing drawings of the buildings ('artists impressions', and plans) to ensure that the building meets the future requirements and is technically feasible (can be built).

[Hotel cartoon]

Similarily a computer system requires analysis before it can be built. As in the case of the building, different models may be used to represent the final structure.

A system may be defined as open, where an interaction occurs with outside environments and closed, where the system is self-contained. [Parker].

There is now an acceptance of the need for long-range planning for information systems.

A business has (or should have) a purpose or mission that identifies current action and long term goals. This strategy should be matched by an 'information strategy' that will support those goals. Part of this information strategy is the data model for the business. This provides the correct data to serve the information system, which in turn supports the corporate strategy.

Model types

There are many ways to represent a system;

graphical - Architectural plans

mathematical - eg. using mathematical formula to represent occupancy

narrative - eg. describing schedule of Quantities (a list of components to build the building)

physical - eg. a 3-D solid model of the proposed structure

To represent the data flow in a system we can use similar tools

graphical - Data Flow Diagrams, Entity Relationship Diagrams, Structure diagrams

mathematical - eg. formulae used to compute tax tables.

narrative - eg. written procedures describing how data is to be input and collected.

physical - eg. a prototype, or demonstration system.

Ref: Management Information Systems: Strategy in Action. C.S.Parker. McGraw-Hill.

Graphical models have proved to be the most easily understood, and with appropriate Computer Assisted Software Engineering (CASE) tools, such as Deft, the construction and manipulation of the diagrams, need not be a paper driven task. Often these tools will allow the construction of the other models (mathematical (process flows), narrative (produces manuals), and physical (prototypes), once the graphical model is developed.