Boundary value analysis is software test design technique. Due to lack of time and cost considerations it is not possible to perform the testing for each set of test data. We look for an adequate and special way of testing techniques which choose the test cases intelligently. One of the techniques we use is Boundary Value testing.
Boundary value analysis is a process of testing between the extreme ends or boundaries of input values. The basic idea of selecting the boundary testing is selecting the input values at their Minimum, just above the Minimum, a nominal value, just below the maximum, a maximum. Boundary Value analysis is a process of testing the boundary input values near the minimum and maximum boundaries. A boundary is an input or output value on the equivalence partition which includes minimum and maximum of inside and outside boundaries. For example suppose we have a very important tool at office which accepts valid user name and password field to work on that tool and accepts minimum 9 characters and maximum 13 characters. Valid range 9 -13, invalid range 8 or less than 8 and invalid range 14 or more than 14.
Boundary value analysis tests the behaviour of the program at boundaries. When we the check a range of data values after selecting the set of data that lie in the valid partitions. The next step is to check how the program behaves in the invalid partitions. Here the common is checking the range of values. For each range, there are two boundaries lower boundary and upper boundary. They are beginning and end of every valid partition. We should design the program in such a way that each test cases should exercise the program functionality at the boundaries and the values with outside and inside the boundaries. Boundary value analysis is another black box type of technique and it is used to find errors in the boundaries in the input domain and the centre of the input. Finding defects using boundary value analysis is very effective technique and it can be used at all levels of testing.
The equivalence class partition and boundary value analysis test design techniques are always used together to determine test data for testing. :
Questions:
1. What is boundary value analysis explain with an example?
2. What is the difference between boundary value testing and equivalence partition testing?