exam 2 ch.8- logical system design

what is the purpose of the system analysis phase

to figure out the business needs

what is the purpose of the system design phase

decide how to build a system that can fulfill those needs

what is the importance of the system analyst role

they are most knowledgeable about the business requirements

what is the importance of a system designer role

database specialists: they advise on database technology

network specialists: advise on network technology

application programmers: experts in new and existing application development tools and standards

what is the objective of system design

it is the recommended solution for a new system

what is included in the system design phase

logical system design

physical system design

what does the logical system design include

the proposed systems

• dfd’s

• erd

the data and process models

• crud matrix

what does the physical system design include

• candidate system solutions matrix

• feasibility analysis matrix

• physical dataflow diagrams

• input and output design

why do system analysts need to synchronize the different views

to make sure there is consistency and completeness of the total system specification

what are the different views of the system

network

data

interface

process models

what is the rule for data stores in data and process model synchronization

there should be one data store in the process model for each entity in the data model

how can the process model maintain the data in the data model

by making sure there are sufficient processes in the process model

what is the data to process (CRUD) matrix

A table that shows the relationship between data (entities) and processes, including how data is used

in the crud matrix what do the rows represent

entities and their attributes as they appear in the propsed system ERD

what do the columns represent in the CRUD matrix

the elementary processes (most detailed) as they appear in the proposed system DFD

what do the cells represent

the level of access a process has to:
create, read, update, delete

what should every entity have

at least one C, R, U, D entry

• if not then it might be omitted from the process models

what does the direction of the dataflow reflect

the action of the process