Definition of a Logical Design

What is a Logical Design?

A logical design is the CONCEPTUAL BLUEPRINT of a software application, illustrating entities, relationships, rules, and processes.

Sample of a Logical Design / Flow Chart

You may have helped create a logical design one without even knowing it.

What may come to mind for many people is a white board full of boxes and arrows created in a live meeting in a business setting. The truth is that almost all of us are involved in a design process whether we know it or not.
When we use Google to search, our search behavior – what we enter and the choices we click on – tells Google developers how to improve the design of their search engine. When presented with a list of ads, we choose the most interesting one. This tells advertisers how to better design their ads. When we stop using Hotmail and switch to Gmail, you could argue that our use of their application or our defection to Gmail is actually helping Microsoft redesign their mail platform.

So what does this have to do with a LOGICAL DESIGN?

First is important to understand that every software application ever produced starts with a logical design.  It is the blueprint guiding the developer.

The logical design tells the developer what processes the application must support, and are usually very detailed.  All software applications model some process, most support hundreds.

Examples of everyday processes that require software, and the require a logical design:

In contrast, a physical design contains things like the following:

• Screenshots
• Mockups
• Server configuration
• Network Configuration
• Device support (Mac, Windows, Mobile)
• Platform support (web, mobile, tablet)
• Software requirements (must support password access to account page, etc)

Other helpful resources explaining the definition of Logical Design

Database Design (wikipedia) excerpt:  Database design is the process of producing a detailed data model of a database. This logical data model contains all the needed logical and physical design choices and physical storage parameters needed to generate a design in a Data Definition Language, which can then be used to create a database

Integration Definition for Information Modeling (wikipedia) excerpt :IDEF1X (Integration Definition for Information Modeling) is a data modeling language for the developing of semantic data models. IDEF1X is used to produce a graphical information model which represents the structure and semantics of information within an environment or system

Logical Versus Physical Database Modeling (developer.com)  excerpt: After all business requirements have been gathered for a proposed database, they must be modeled. Models are created to visually represent the proposed database so that business requirements can easily be associated with database objects to ensure that all requirements have been completely and accurately gathered. Different types of diagrams are typically produced to illustrate the business processes, rules, entities, and organizational units that have been identified.

About the author

Keven M. Thibeault has been developing applications since 1990.  He now serves as principal and CEO at Logical Design Database Solutions based in Boston, Mass, and provides product strategy and expert application development services for web, mobile, tablet, and enterprise platforms targeting startups, interactive agencies, and technology clients.