Understanding Data Flow Diagrams

Which of the following is NOT a basic component of a Data Flow Diagram (DFD)?

• Data Store

• Process

• Data Flow

• Algorithm

In a Data Flow Diagram, which symbol is typically used to represent a process?

• Rectangle

• Circle or rounded rectangle

• Double line

• Arrow

What does a double horizontal line represent in a Data Flow Diagram?

• Data Store

• External Entity

• Data Flow

• Process

Which of the following best describes a 'levelled' Data Flow Diagram?

• A DFD that uses only one level of detail

• A DFD that breaks down processes into more detailed sub-processes across multiple levels

• A DFD that only shows data stores

• A DFD that uses colour coding

In DFD notation, what does an arrow indicate?

• The direction of data flow between components

• The start of a process

• The end of a process

• The storage of data

Which of the following is the correct symbol for an external entity in a DFD?

• Square or rectangle

• Circle

• Double horizontal line

• Dashed line

What is the main purpose of using different levels (e.g., Level 0, Level 1) in Data Flow Diagrams?

• To show the physical layout of a system

• To provide increasing detail about system processes

• To indicate the speed of data flow

• To represent different users

Which of the following statements about Data Flow Diagrams is TRUE?

• DFDs are used to model the physical design of a system

• DFDs show how data moves through a system

• DFDs are only used for database design

• DFDs do not use symbols

In a DFD, which component is responsible for transforming input data into output data?

• Data Store

• Process

• External Entity

• Data Flow

Which of the following is NOT a standard rule when drawing Data Flow Diagrams?

• Each process must have at least one input and one output

• Data cannot flow directly between two data stores

• Data can flow directly from an external entity to another external entity

• Data must flow through a process to move between data stores and external entities