This paper examines the systems development life cycle (SDLC) as it applies to database systems. It defines the key phases of the SDLC — from initial concept and feasibility study through requirements analysis, design, development, testing, implementation, and maintenance — and explains why each phase is essential. The paper then connects SDLC principles to database planning, illustrating how the two frameworks share a core iterative structure. Finally, it considers how organizations of different sizes should approach SDLC methodology selection, arguing that small companies benefit from a unified approach while larger organizations may adopt diverse methodologies across divisions.
The systems development life cycle (SDLC) in systems engineering refers to a framework that addresses all phases of the engineering process. These phases include system conception, design and development, production and/or construction, distribution, operation, maintenance and support, retirement, phase-out, and disposal. Because every system is created to fulfill a specific purpose and eventually becomes obsolete or is replaced by a more effective solution, systems inherently have both a beginning and an end. The SDLC provides a structured path through that lifespan.
The SDLC is composed of several distinct phases, each of which plays a critical role in the overall development process.
1. Initial Idea: This phase concerns what the project is about, its purpose, and the ways of accomplishing it. It establishes the vision that will guide all subsequent stages.
2. Feasibility Study: This phase addresses how long the project should take, its scope, and its deadline. It is typically carried out by management, who assess the feasibility of the idea in terms of economic and organizational factors. Smaller projects may omit this stage.
3. Requirements Analysis: This phase identifies the business options available to address a problem. It may be supported by technical documents such as high-level data flow diagrams (DFDs), Logical Data Models (LDMs), and Work Practice Models, and it accounts for financial and other risks.
4. Systems Analysis and Specifications: This phase produces a logical model of the system and provides precise details of what the system will do, without yet specifying how it will do it.
5. Systems Design: This stage addresses how the system's requirements will be implemented. Multiple designs are generated, and the one that most closely matches the original idea while minimizing cost, complexity, and labor is selected.
6. Development: Program code is written during this phase. Each unit is tested individually to ensure it meets the defined specifications.
7. Testing: The life cycle incorporates several layers of testing:
Unit testing — performed during the development stage to verify individual components.
Link testing — verifies that all programs work well together.
System testing — confirms that the system as a whole performs correctly.
User acceptance testing — conducted by end users to ensure the system is usable and meets their needs.
Any required modifications are incorporated into a revised design.
8. Implementation: The system is deployed either in a phased approach (introduced cautiously in stages) or via a "big bang" approach (all at once). The process of migrating data from the old system to the new one is called conversion.
9. Maintenance and Review: A well-functioning and reliable system requires continuous review to ensure it remains effective and aligned with organizational needs.
The database is the core component of an information system, which means that database design is inherently a part of systems development. The database planning process incorporates many of the key elements of the systems life cycle. It begins with database planning — corresponding to the initial idea — and proceeds through implementation, testing, and monitoring, with a loop-back process of analysis and design. The core steps are structurally similar to those of the SDLC.
The SDLC supports database development by helping the researcher formulate an initial idea, conduct a feasibility study, analyze requirements, and perform a systems analysis. It then guides the developer through specifying outcomes from that analysis, implementing a systems design, proceeding to the development stage, and testing the system. Once testing is approved, the process moves into implementation, followed by maintenance and review. Importantly, the cycle loops back to the initial idea to determine whether the finished product coheres with the original vision or requires fine-tuning or a return to the drawing board.
In both the SDLC and database planning frameworks, the loop-back mechanism is a deliberate design feature. It ensures that the final product remains aligned with the original goals and that no stage proceeds unchecked.
"Explains why SDLC is essential as a blueprint"
"Compares SDLC approaches for small vs. large organizations"
In a larger company, it is important for each division to have slightly different software development life cycles, since the goals, behaviors, and tasks of each division differ and the SDLC needs to help them accomplish those tasks. A diversity of approaches to software development can be healthy in a large organization because it allows for flexibility and reflects the inherent diversity of the company's operations. A small company, however, would not only risk squandering resources on multiple SDLC programs, but would also introduce conflict rather than the consistency and creativity that a unified approach can provide.
You’re 67% through this paper. Sign up to read the remaining 2 sections.
Sign Up Now — Instant Access Already a member? Log inAlways verify citation format against your institution’s current style guide requirements.