Presentation on DFD and System Analyst.pptx

presentation of data flow diagram

1. System Analyst and DFD PRESENTED BY Ichchha Ramtel Janis Adhikari Dikshant Shrestha Madav Acharya National College of Management and Technical Science Samakhushi, Kathmandu PRESENTATION ON 2024/08/24

2. Table of content System Analyst Role of system Analyst Skills required for system analyst Data flow diagram Component of DFD Levels of DFD Guidelines for creating DFD Benefits of DFD Limitations of DFD Practical Applications of DFD

3. System Analyst System Analysis is the process of studying and understanding a system, identifying its components, and designing solutions to improve its efficiency. A System Analyst is a professional who uses analysis and design techniques to solve business problems using information technology. To bridge the gap between business needs and IT solutions.

4. Role of System analyst Requirement gathering System design System implementation System testing Documentation Trouble shooting and support

5. Skills required for a system analyst Technical skills Analytical skills Communication skills Problem skills Project management

6. Data Flow Diagram (DFD) A data flow diagram (DFD) is a graphical representation of the movement of data between external entities, processes and data stores within a system Simply put, DFD’s show how data moves through an information system.

7. Components of DFD Source/Sinks (External Entity) Process Data store Dataflow

8. External Entity (Source/Sink) People or organization that sends or receive data into or from system It is denoted by Rectangle symbol. For example , Customer in a E-commerce system. Customer

9. Process Represent tasks, activities, or functions where data is processed. Each process transforms incoming data into outgoing data. It is represented by Circle or rounded Rectangle For example: Order process in E-commerce software Order Orders OR

10. Data Store Represent places where data is stored within the system. This could be a database, a file, or any repository. It is represented by open ended rectangle or two parallel line Data store Data Store OR

11. Data flow Represent the movement of data between processes, data stores, and external entities. Represented by arrow The direction of the arrow indicates the flow of data

12. Levels of DFD Level 0 DFD: Represents the highest level of abstraction, showing the system as a single process with external entities. Level 1 DFD: Breaks down the system into major processes and shows the interactions between them. Level 2 DFD: Further decomposes the processes into sub-processes to provide more detailed information.

13. Guidelines for creating DFD Process Flows:  Each process must have at least one outgoing and one ingoing data flow. Data Store Connectivity:  Data stores should have at least one incoming and outgoing data flow. Entity-Process Link:  Entities must be connected to a process by a data flow. Avoiding Crossings:  Data flows cannot cross with each other. External Entity Access:  Data stores cannot directly connect to external entities.

14. Benefit of DFD A graphical technique that is relatively easy to understand for stakeholders and other users. Provides a detailed view of the system components and boundaries. Provide clear and detailed information about the processes within a system. Shows the logic of the data flow. Presents a functional breakdown of the system. Used as a part of the system documentation.

15. Limitations of Data Flow Diagram 1. Lack of Detail:DFDs provide a broad overview of a system and its data flows, but they do not capture the details of how data is processed within each process. This can lead to an oversimplified understanding of the system. 2. Ambiguity:DFDs can be interpreted differently by different people because there is no strict standardization in terms of symbols and notations. This ambiguity can cause miscommunication among stakeholders. 3. Lack of Control Information:DFDs do not represent the control flow or decision logic within the system, making it difficult to understand the conditional paths that might exist.

16. 4. Scalability Issues:For large systems, DFDs can become extremely complex and hard to manage, leading to diagrams that are difficult to understand and maintain. 5. Not Suitable for All Systems:DFDs are not well-suited for systems where data flow is not the primary concern, such as systems that are more focused on complex algorithms or user interfaces. 6. Maintenance Challenges:As the system evolves, keeping the DFD up to date can be challenging. Changes in the system require the DFD to be revised, which can be time-consuming.

17. Practical Application of DFD 1.Requirement Analysis: During the initial stages of system development, DFDs are used to capture the functional requirements of a system. They help in understanding the data inputs, processes, and outputs of the system, providing a clear picture of the business processes and information flow. 2.Process Improvement: Businesses use DFDs to model and analyze their existing processes. By mapping out how data flows through different business functions, organizations can identify bottlenecks, inefficiencies, and areas for improvement.

18. 3.Documentation: DFDs serve as part of the system documentation, providing a visual reference that can be used throughout the software development lifecycle. This is especially useful for maintaining and updating systems over time. 4.Data Modeling: DFDs are used to identify the data needs of a system and how data should be organized. They help in designing the structure of databases by showing how data flows into and out of various data stores. 5.Quality Assurance: In quality assurance processes, DFDs are used to verify that the system’s design aligns with the business requirements and that data flows as expected. 6.Progress Tracking: DFDs help in tracking the progress of system development by serving as a reference point for what has been completed and what is still in progress.