Explain the differences between Gane and Sarson and Yourdon symbols. Provide examples of symbols that represent processes, data flows, data stores, and entities.

Question

What will be an ideal response?

Answer 1

• The Gane and Sarson symbol for a process is a rectangle with rounded corners, while the Yourdon symbol is a circle. The name of the process is placed inside the symbol.
• Both symbol sets show a data flow as a line with an arrowhead, with the name of the data flow placed above, below, or alongside the line. The line’s arrowhead shows the direction in which the data flows.
• The Gane and Sarson symbol for a data store is a flat rectangle open on the right side. The Yourdon symbol is two parallel lines. The name of the data store is placed inside the symbol.
• An external entity is a person, department, outside organization, or other information system that provides data to the system or receives output from the system. The symbol for an external entity in both sets is a square. The Gane and Sarson symbol usually is shaded, and the name of the external entity is placed inside the symbol.
• Examples of process names are APPLY RENT PAYMENT, CALCULATE COMMISSION, ASSIGN FINAL GRADE, VERIFY ORDER, and FILL ORDER.
• Examples of data flow names are DEPOSIT, INVOICE PAYMENT, STUDENT GRADE, ORDER, and COMMISSION.
• Typical data store names might include PAYROLL ITEMS, CLASS ROSTER, INVENTORY LIST, and COURSE SCHEDULE
• Some examples of entity names might be CUSTOMER, BANK, VENDOR, or ACCOUNTING SYSTEM.