System Analysis

System analysis involves examining the existing system in detail. The system analyst must find out why the system has to be changed, by:

1.  Collecting information on how the existing system works

2.  Establish the input, output and processing

3.  Recording information

4.  And finally, identifying the problem

The first stage in system analysis, the system analyst has to collect information about how the is the current system so he will use these four methods:

1.  Examining of documents

2.  Interviews

3.  Observation

4.  Questionnaires

After the system analyst has finished collecting the information he needs to identify the input, output and processing and quit often this stage is done whilst producing a data flow diagram.

The system analyst needs now to record all the results in order to establish all the relevant features of the existing system.

Data flow diagram is a graphical method of recording the inputs, outputs and processing that have been identified.

It consists of four components:

1.  Terminator

2.  Processes

3.  Flow arrows

4.  Stores

Data flow chart is a generally a method of designing a systems solution and so is not found very frequently in the analysis stage.

Now the system analyst can identify the problems in the old system. Since he used the system data flow chart, it helped him to identify the problems.

After the data flow diagram  have been produced they are examined together with the other results of analysis such as interview transcripts and questionnaire analysis to identify the problems with the current system.

References:

Tech-ict.com

Ict book (AS level and A level)