basically we have write the testcases with the help of performance requirements and usecases.
as per ur requirements there is no related requirements documents.In that time we are following the which is frequently used transaction and which are not frequently used transactions. Based upon these u have write the test cases.1)what's the response time of server with mininmum users.
2)what's the response time of server with maximum users and as per requirements.
3)how much time taken by particular transaction.
4)what's the peak load and time
With my 2 years of experience in this field i say , there is no fixed procedure to learn the art of writing a test case.it all devlops with you working out on this ,try writing as much test cases as you can in the initial stage.May be you are writing 15 test cases for a function which actually requires only 2 .Just go ahead boss you will learn the art of reducing and making your cases effective.You can just try write some of them and paste it here , i am sure people will help you out here to improvise it.Best of luck
IMHO it is futile/time consuming to write test cases for every function within the application unless your are clear with requirements. Instead try to understand what the application is for or better try to step into user's shoes and explore the application. Once you get little info on the purpose of application, try writing test cases to cover those aspects which you think important.
Quality means doing it right when no one is looking. - Henry Ford.
I would suggest that in order to write good test cases, understand first what you are testing and what kinds of testing your project manager, developer and customer/users are expecting to be completed.
We can't test everything but you want to cover as much as you can with regards to the expectations of the project. Talk with your project manager or who gave you this assignment. Ask for a specific list of what is to be tested i.e.: performance, functions, how to use the application, appearance, how to use overall, how functions work together or if the application works with other applications, etc.
Until you understand what types of testing are necessary to meet the expectations, you will not be able to write test cases that will work for your project.
Be careful using the term "writing a good test case" because it's not as simple as that.