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Testing Interview Questions Answers

Testing Interview Question - 1 : -

What if the project isn't big enough to justify extensive testing?

Testing Interview Answer - 1 : -

Consider the impact of project errors, not the size of the project. However, if extensive testing is still not justified, risk analysis is again needed and the same considerations as described previously in 'What if there isn't enough time for thorough testing?' apply. The tester might then do ad hoc testing, or write up a limited test plan based on the risk analysis.
 

Testing Interview Question - 2 : -

Why does software have bugs?

Testing Interview Answer - 2 : -

• miscommunication or no communication - as to specifics of what an application should or shouldn't do (the application's requirements).
• software complexity - the complexity of current software applications can be difficult to comprehend for anyone without experience in modern-day software development. Windows-type interfaces, client-server and distributed applications, data communications, enormous relational databases, and sheer size of applications have all contributed to the exponential growth in software/system complexity. And the use of object-oriented techniques can complicate instead of simplify a project unless it is well-engineered.
• programming errors - programmers, like anyone else, can make mistakes.
• changing requirements (whether documented or undocumented) - the customer may not understand the effects of changes, or may understand and request them anyway - redesign, rescheduling of engineers, effects on other projects, work already completed that may have to be redone or thrown out, hardware requirements that may be affected, etc. If there are many minor changes or any major changes, known and unknown dependencies among parts of the project are likely to interact and cause problems, and the complexity of coordinating changes may result in errors. Enthusiasm of engineering staff may be affected. In some fast-changing business environments, continuously modified requirements may be a fact of life. In this case, management must understand the resulting risks, and QA and test engineers must adapt and plan for continuous extensive testing to keep the inevitable bugs from running out of control - see 'What can be done if requirements are changing continuously?' in Part 2 of the FAQ.
• time pressures - scheduling of software projects is difficult at best, often requiring a lot of guesswork. When deadlines loom and the crunch comes, mistakes will be made.
• egos - people prefer to say things like:
'no problem'
'piece of cake'
'I can whip that out in a few hours'
'it should be easy to update that old code'
instead of:
'that adds a lot of complexity and we could end up
making a lot of mistakes'
'we have no idea if we can do that; we'll wing it'
'I can't estimate how long it will take, until I
take a close look at it'
'we can't figure out what that old spaghetti code
did i

 

Testing Interview Question - 3 : -

What if there isn't enough time for thorough testing?

Testing Interview Answer - 3 : -

Use risk analysis to determine where testing should be focused.
Since it's rarely possible to test every possible aspect of an application, every possible combination of events, every dependency, or everything that could go wrong, risk analysis is appropriate to most software development projects. This requires judgement skills, common sense, and experience. (If warranted, formal methods are also available.) Considerations can include:
• Which functionality is most important to the project's intended purpose?
• Which functionality is most visible to the user?
• Which functionality has the largest safety impact?
• Which functionality has the largest financial impact on users?
• Which aspects of the application are most important to the customer?
• Which aspects of the application can be tested early in the development cycle?
• Which parts of the code are most complex, and thus most subject to errors?
• Which parts of the application were developed in rush or panic mode?
• Which aspects of similar/related previous projects caused problems?
• Which aspects of similar/related previous projects had large maintenance expenses?
• Which parts of the requirements and design are unclear or poorly thought out?
• What do the developers think are the highest-risk aspects of the application?
• What kinds of problems would cause the worst publicity?
• What kinds of problems would cause the most customer service complaints?
• What kinds of tests could easily cover multiple functionalities?
• Which tests will have the best high-risk-coverage to time-required ratio?
 

Testing Interview Question - 4 : -

What's the big deal about 'requirements'?

Testing Interview Answer - 4 : -

One of the most reliable methods of insuring problems, or failure, in a complex software project is to have poorly documented requirements specifications. Requirements are the details describing an application's externally-perceived functionality and properties. Requirements should be clear, complete, reasonably detailed, cohesive, attainable, and testable. A non-testable requirement would be, for example, 'user-friendly' (too subjective). A testable requirement would be something like 'the user must enter their previously-assigned password to access the application'. Determining and organizing requirements details in a useful and efficient way can be a difficult effort; different methods are available depending on the particular project. Many books are available that describe various approaches to this task. (See the Bookstore section's 'Software Requirements Engineering' category for books on Software Requirements.)
Care should be taken to involve ALL of a project's significant 'customers' in the requirements process. 'Customers' could be in-house personnel or out, and could include end-users, customer acceptance testers, customer contract officers, customer management, future software maintenance engineers, salespeople, etc. Anyone who could later derail the project if their expectations aren't met should be included if possible.
Organizations vary considerably in their handling of requirements specifications. Ideally, the requirements are spelled out in a document with statements such as 'The product shall.....'. 'Design' specifications should not be confused with 'requirements'; design specifications should be traceable back to the requirements.
In some organizations requirements may end up in high level project plans, functional specification documents, in design documents, or in other documents at various levels of detail. No matter what they are called, some type of documentation with detailed requirements will be needed by testers in order to properly plan and execute tests. Without such documentation, there will be no clear-cut way to determine if a software application is performing correctly.
'Agile' methods such as XP use methods requiring close interaction and cooperation between programmers and customers/end-users to iteratively develop requirements. The programmer uses 'Test first' development to first create automated unit testing code, which essentially embodies the requirements.
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Testing Interview Question - 5 : -

What's an 'inspection'?

Testing Interview Answer - 5 : -

An inspection is more formalized than a 'walkthrough', typically with 3-8 people including a moderator, reader, and a recorder to take notes. The subject of the inspection is typically a document such as a requirements spec or a test plan, and the purpose is to find problems and see what's missing, not to fix anything. Attendees should prepare for this type of meeting by reading thru the document; most problems will be found during this preparation. The result of the inspection meeting should be a written report. Thorough preparation for inspections is difficult, painstaking work, but is one of the most cost effective methods of ensuring quality. Employees who are most skilled at inspections are like the 'eldest brother' in the parable in 'Why is it often hard for management to get serious about quality assurance?'. Their skill may have low visibility but they are extremely valuable to any software development organization, since bug prevention is far more cost-effective than bug detection.
 

Testing Interview Question - 6 : -

What are some recent major computer system failures caused by software bugs?

Testing Interview Answer - 6 : -

• A major U.S. retailer was reportedly hit with a large government fine in October of 2003 due to web site errors that enabled customers to view one anothers' online orders.
• News stories in the fall of 2003 stated that a manufacturing company recalled all their transportation products in order to fix a software problem causing instability in certain circumstances. The company found and reported the bug itself and initiated the recall procedure in which a software upgrade fixed the problems.
• In August of 2003 a U.S. court ruled that a lawsuit against a large online brokerage company could proceed; the lawsuit reportedly involved claims that the company was not fixing system problems that sometimes resulted in failed stock trades, based on the experiences of 4 plaintiffs during an 8-month period. A previous lower court's ruling that "...six miscues out of more than 400 trades does not indicate negligence." was invalidated.
• In April of 2003 it was announced that the largest student loan company in the U.S. made a software error in calculating the monthly payments on 800,000 loans. Although borrowers were to be notified of an increase in their required payments, the company will still reportedly lose $8 million in interest. The error was uncovered when borrowers began reporting inconsistencies in their bills.
• News reports in February of 2003 revealed that the U.S. Treasury Department mailed 50,000 Social Security checks without any beneficiary names. A spokesperson indicated that the missing names were due to an error in a software change. Replacement checks were subsequently mailed out with the problem corrected, and recipients were then able to cash their Social Security checks.
• In March of 2002 it was reported that software bugs in Britain's national tax system resulted in more than 100,000 erroneous tax overcharges. The problem was partly attibuted to the difficulty of testing the integration of multiple systems.
• A newspaper columnist reported in July 2001 that a serious flaw was found in off-the-shelf software that had long been used in systems for tracking certain U.S. nuclear materials. The same software had been recently donated to another country to be used in tracking their own nuclear materials, and it was not until scientists in that country discovered the problem, and shared the information, that U.S. officials became aware o
 

Testing Interview Question - 7 : -

How can new Software QA processes be introduced in an existing organization?

Testing Interview Answer - 7 : -

• A lot depends on the size of the organization and the risks involved. For large organizations with high-risk (in terms of lives or property) projects, serious management buy-in is required and a formalized QA process is necessary.
• Where the risk is lower, management and organizational buy-in and QA implementation may be a slower, step-at-a-time process. QA processes should be balanced with productivity so as to keep bureaucracy from getting out of hand.
• For small groups or projects, a more ad-hoc process may be appropriate, depending on the type of customers and projects. A lot will depend on team leads or managers, feedback to developers, and ensuring adequate communications among customers, managers, developers, and testers.
• The most value for effort will be in (a) requirements management processes, with a goal of clear, complete, testable requirement specifications embodied in requirements or design documentation and (b) design inspections and code inspections.
 

Testing Interview Question - 8 : -

What is a 'walkthrough'?

Testing Interview Answer - 8 : -

A 'walkthrough' is an informal meeting for evaluation or informational purposes. Little or no preparation is usually required.
 

Testing Interview Question - 9 : -

What are 5 common solutions to software development problems?

Testing Interview Answer - 9 : -

• solid requirements - clear, complete, detailed, cohesive, attainable, testable requirements that are agreed to by all players. Use prototypes to help nail down requirements.
• realistic schedules - allow adequate time for planning, design, testing, bug fixing, re-testing, changes, and documentation; personnel should be able to complete the project without burning out.
• adequate testing - start testing early on, re-test after fixes or changes, plan for adequate time for testing and bug-fixing.
• stick to initial requirements as much as possible - be prepared to defend against changes and additions once development has begun, and be prepared to explain consequences. If changes are necessary, they should be adequately reflected in related schedule changes. If possible, use rapid prototyping during the design phase so that customers can see what to expect. This will provide them a higher comfort level with their requirements decisions and minimize changes later on.
• communication - require walkthroughs and inspections when appropriate; make extensive use of group communication tools - e-mail, groupware, networked bug-tracking tools and change management tools, intranet capabilities, etc.; insure that documentation is available and up-to-date - preferably electronic, not paper; promote teamwork and cooperation; use protoypes early on so that customers' expectations are clarified.
 

Testing Interview Question - 10 : -

What is 'Software Quality Assurance'?

Testing Interview Answer - 10 : -

Software QA involves the entire software development PROCESS - monitoring and improving the process, making sure that any agreed-upon standards and procedures are followed, and ensuring that problems are found and dealt with. It is oriented to 'prevention'. (See the Bookstore section's 'Software QA' category for a list of useful books on Software Quality Assurance.)
 

Testing Interview Question - 11 : -

How is testing affected by object-oriented designs?

Testing Interview Answer - 11 : -

Well-engineered object-oriented design can make it easier to trace from code to internal design to functional design to requirements. While there will be little affect on black box testing (where an understanding of the internal design of the application is unnecessary), white-box testing can be oriented to the application's objects. If the application was well-designed this can simplify test design.
 

Testing Interview Question - 12 : -

How can World Wide Web sites be tested?

Testing Interview Answer - 12 : -

Web sites are essentially client/server applications - with web servers and 'browser' clients. Consideration should be given to the interactions between html pages, TCP/IP communications, Internet connections, firewalls, applications that run in web pages (such as applets, javascript, plug-in applications), and applications that run on the server side (such as cgi scripts, database interfaces, logging applications, dynamic page generators, asp, etc.). Additionally, there are a wide variety of servers and browsers, various versions of each, small but sometimes significant differences between them, variations in connection speeds, rapidly changing technologies, and multiple standards and protocols. The end result is that testing for web sites can become a major ongoing effort. Other considerations might include:
• What are the expected loads on the server (e.g., number of hits per unit time?), and what kind of performance is required under such loads (such as web server response time, database query response times). What kinds of tools will be needed for performance testing (such as web load testing tools, other tools already in house that can be adapted, web robot downloading tools, etc.)?
• Who is the target audience? What kind of browsers will they be using? What kind of connection speeds will they by using? Are they intra- organization (thus with likely high connection speeds and similar browsers) or Internet-wide (thus with a wide variety of connection speeds and browser types)?
• What kind of performance is expected on the client side (e.g., how fast should pages appear, how fast should animations, applets, etc. load and run)?
• Will down time for server and content maintenance/upgrades be allowed? how much?
• What kinds of security (firewalls, encryptions, passwords, etc.) will be required and what is it expected to do? How can it be tested?
• How reliable are the site's Internet connections required to be? And how does that affect backup system or redundant connection requirements and testing?
• What processes will be required to manage updates to the web site's content, and what are the requirements for maintaining, tracking, and controlling page content, graphics, links, etc.?
• Which HTML specification will be adhered to? How strictly? What variations will be allowed for targeted browsers?
• Will there be any s

 

Testing Interview Question - 13 : -

How does a client/server environment affect testing?

Testing Interview Answer - 13 : -

Client/server applications can be quite complex due to the multiple dependencies among clients, data communications, hardware, and servers. Thus testing requirements can be extensive. When time is limited (as it usually is) the focus should be on integration and system testing. Additionally, load/stress/performance testing may be useful in determining client/server application limitations and capabilities. There are commercial tools to assist with such testing. (See the 'Tools' section for web resources with listings that include these kinds of test tools.)
 

Testing Interview Question - 14 : -

How can Software QA processes be implemented without stifling productivity?

Testing Interview Answer - 14 : -

By implementing QA processes slowly over time, using consensus to reach agreement on processes, and adjusting and experimenting as an organization grows and matures, productivity will be improved instead of stifled. Problem prevention will lessen the need for problem detection, panics and burn-out will decrease, and there will be improved focus and less wasted effort. At the same time, attempts should be made to keep processes simple and efficient, minimize paperwork, promote computer-based processes and automated tracking and reporting, minimize time required in meetings, and promote training as part of the QA process. However, no one - especially talented technical types - likes rules or bureacracy, and in the short run things may slow down a bit. A typical scenario would be that more days of planning and development will be needed, but less time will be required for late-night bug-fixing and calming of irate customers.
 

Testing Interview Question - 15 : -

What is software 'quality'?

Testing Interview Answer - 15 : -

Quality software is reasonably bug-free, delivered on time and within budget, meets requirements and/or expectations, and is maintainable. However, quality is obviously a subjective term. It will depend on who the 'customer' is and their overall influence in the scheme of things. A wide-angle view of the 'customers' of a software development project might include end-users, customer acceptance testers, customer contract officers, customer management, the development organization's management/accountants/testers/salespeople, future software maintenance engineers, stockholders, magazine columnists, etc. Each type of 'customer' will have their own slant on 'quality' - the accounting department might define quality in terms of profits while an end-user might define quality as user-friendly and bug-free.