What is a data-flow diagram (DFD)?

• A way of representing a flow of data of a process or a system

• A type of flowchart

• A method for data storage

• A programming language

What are the four basic symbols used in DFD?

• Process, Data Store, External Entity, Data Flow

• Input, Output, Process, Storage

• Circle, Square, Triangle, Arrow

• Entity, Relationship, Attribute, Flow

What does the top-down decomposition technique in DFD show?

• More detail in lower-level DFDs

• Only high-level processes

• The final output of a system

• The data storage methods

What is the highest level in the hierarchy of DFDs?

• Context Diagram

• Level 1 DFD

• Level 2 DFD

• Zero Level DFD

What is the purpose of a flowchart?

• To break down a complex process into simple steps

• To represent data flow

• To store data

• To create a database

What is the unique attribute of the Yourdon and Coad DFD notation?

• A data store is represented as two parallel, horizontal lines

• Processes are represented by a square

• It uses only one symbol

• It does not include data flow

What does the Gane-Sarson notation represent?

• Data flow diagrams

• Flowcharts

• Database schemas

• Programming languages

What are the four basic symbols used in data flow diagrams?

• double square

• arrow

• rectangle with rounded corners

• open-ended rectangle

What do entities represent in a data flow diagram?

• People, organizations, or other things that interact with the system

• Processes that change the data

• Data stores that contain information

• Data flows that map out inputs and outputs

What is the purpose of processes in a data flow diagram?

• To represent actions that change the data

• To represent data stores

• To represent entities

• To represent data flows