A system analyst has been in charge of creating an automatic production line for a factory
The analyst followed the stages of the system life cycle. Describe the purpose of the three stages of the system life cycle which must be complete before design starts.
The first thing they must do is a project planning such as feasibility study which is where they look at what can happen, they need to see if it is feasible within the cost, time and i f it can make a profit. they will also look at skill needed to build and it and the training needed to use it
the second stage will be system analysis/ investigation and analysis, this is were they will refine the project goals into defined functions and operation of intended. they can carry out face to interview and questionnaires to gain more information on how best to approach and build the intended project.
the third stage is user requirement. this will not define hardware or software but looks at what needs to be done. it is more to see what the users wants and needs.
What is the waterfall model of the system life cycle?
in the traditional waterfall model each stage must be completed before the other phase can commence. the result is that each page or section needs its own mini life cycle. once it has began and for example a stage has been completed, just like a waterfall it cannot go back to and earlier stage just like ho a waterfall cannot just stop and go back to and earlier stage.
items bought at a supermarket are passed over a scanner
describe how the system can use the information to control levels of stock
When the stock is first entered into the store is marked into the computer through files where is stored on the computer so that it can be accessed at any time. it means that when an item is being bought it is scanned through using a barcode scanner, all items have a barcode as it make it quicker to put through a computer system and also enables the supermarket to keep track of what goes in and out of the store. Once the item is scanned it will send a message to the computer so that the number of that product can be changed to the correct number. This means that when the stock get low it can send an alert to inform them that their stock is low or in some supermarket automatically order more of the stock back in. this also allows them to see what is popular and what is not so that they can see what they should keep in stock and what they should stop selling
a supermarket stores data about costumers who have loyalty cards
explain why some customers may be concerned about giving away their personal data to the supermarket.
when giving away informations they may be concerned of personal information being lost and so their information might be used by companies trying to sell or even trick them into giving details away such as bank details, also they may not ant to get bombarded by leaflet and information from these companies.
describe steps the supermarket can take to reassure customers about their concerns
the company could insert special security meassures and demonstrate to their customers how it works so that they can see that it is safe.
TEST DATA- black box and white box testing. in black box testing their is invalid data, valid data and borderline data. invalid data is data which should generate an error message if it was input outside of the expected range. valid data is data that you would normally expect the user to input within the expected range. finally borderline data is data where you need to be extremely careful to test it at the boundaries of different cases, to ensure they are dealt with correctly.
it is also important that any data testing which checks the validation should include the following: normal data-which is data that is in the normal range and will be accepted
extreme data- data that is on the extreme limits but should be accepted. for example if the borderline was 100 and you had 100 it will just about be accepted.
erroneous data-data that should fail if tested
TEST TABLES- is a table outlining the test plan. the heading in order are test number, part of system, test data, expected results, actual results and pass/fail.
DEBUGGING tools-it is a process of locating and getting rid of bugs from the computer.
TRANSLATOR DIAGNOSTICS-messages generated by the translator, while translating the source code and object code. it is used to find syntax and logic errors
trace tables are used by programmers to track the values of variables as they change throughout the program. this is useful when a program is not producing the desired results.
The first test of newly developed hardware or software in a laboratory setting. When the first round of bugs has been fixed, the product goes into beta test with actual users. For custom software, the customer may be invited into the vendor’s facilities for an alpha test to ensure the client’s vision has been interpreted properly by the developer. See beta test and testing types
for example when companies are developing videos game they first text the game in their own labs where they can make sure it actuals does what is is meant to do, then they use beta testing when they realise it for public to use and play so they can test how it performs in a real life situation