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Tuesday, November 10, 2009

Lessons Learned from Pradeep Soundararajan

Chapter 2 - Kids can do Boundary Value Analysis!!

My niece is 5 years old. She doesn't know what is software testing, in fact she doesn't know what is software but still she can do Boundary Value Analysis. Amazing na.... although I have never asked her to do so but still I am sure that she can do it.

Surely, you will be surprised how I am so sure? Actually, she can add the numbers, subtract the numbers and that is exactly what most of us do on the name of Boundary Value Analysis.

I was also following the same approach until Pradeep Sir has not mentioned it in one of his workshop. The question is - Are we really doing analysis?

The Wikipedia says:
Analysis is the process of breaking a complex topic or substance into smaller parts to gain a better understanding of it.

As definition says Analysis is just not adding or subtracting 1. It seems that we have changed the definition of analysis. If what we are doing is analysis then perhaps the software testers at NASA are doing the same :) They are just adding and subtracting the numbers. If that so, any body who can do addition and subtraction can join panel of Software Testers in NASA.

Boundary value analysis is a software testing design technique in which tests are designed to include representatives of boundary values. Values on the edge of an equivalence partition or at the smallest value on either side of an edge. The values could be either input or output ranges of a software component.

The definition doesn't mention +1/-1 approach. It also doesn't tell us that BVA can be be applied on input fields only which we generally do.

It is said that most of the bugs reside on the boundaries. Don't know who made this statement. Might be a tester has made the statement when he found most of the bugs at the boundaries when he was testing an application.

But is he right?

Might be he is right but did he really applied the +1/-1 approach. I don't think so. Check out the total bugs logged by you and then see how many bugs you have found by +1/-1 approach. I am sure the percentage would be very low.

Perhaps we are misunderstanding the concept of Boundary Value Analysis or Might be we need to rename the +1/-1 approach. How about calling it “Kids Approach”.

Think about it tell then let me try to find out what is Boundary Value Analysis?

3 comments:

Pradeep Soundararajan said...

I am glad you blog because it helps me understand how you understood things.

+1/-1 has been useful in finding bugs that caused problems and news however the hype around it and the importance given to it surpasses anything else.

I know of quite a few people who think if they can explain or write down what BVA and ECP means, they are likely to be regarded as testers.

I don't think its possible and that is what I oppose.

Plus, boundary, means a lot of things. I am surprised those who talk about boundary analysis themselves appear to not analyze the boundary of their thinking about boundaries.

Santhosh Tuppad said...

@Pradeep Soundararajan,
You are absolutely right. Even those who claim to be professionals define it as "+1 / -1 " which is incorrect. If this is the case then it is just verifying +1 and -1 and not analysis of the boundary. And this is important question in most of the interviews that interviewers think which is correct but the answers they are expecting is not that important nor talk about analysis *smiles*.

Thanks,
Santhosh Shivanand Tuppad

Unknown said...

Can you explain concisely what exactly is this boundary value analysis ?