ISBN : 978-81-963532-2-3 (E-Book) Fig.11.2:StructureChart TransactionAnalysis A transaction allows the user to perform some meaningful piece of work. Transaction analysisis useful while designing transaction processing programs. In a transaction-driven system, oneof several possible paths through the DFD is traversed depending upon the input data item.This is in contrast to a transform centered system which is characterized by similar processingsteps for each data item. Each different way in which input data is handled is a transaction. Asimple way to identify a transaction is to check the input data. The number of bubbles onwhich the input data to the DFD are incident defines the number of transactions. However,some transaction may not require any input data. These transactions can be identified from theexperienceof solvingalargenumber ofexamples. For each identified transaction, trace the input data to the output. All the traversed bubblesbelongtothetransaction.Thesebubblesshouldbemappedtothesamemoduleonthestructure 53 Software Engineering Keerthana P, Manasa KN, Ganga D Bengal
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