Software Testing interview questions
Given the following code, which statement is true about the minimum number of test cases required for full statement and branch coverage? Read p Read q IF p+q> 100 THEN Print "Large" ENDIF IF p > 50 THEN Print "p Large" ENDIF
1 test for statement coverage, 2 for branch coverage
An input field takes the year of birth between 1900 and 2004 what are the boundary values for testing this field?
1899,1900,2004,2005
Given the following fragment of code, how many tests are required for 100% decision coverage? if width > length thenbiggest_dimension = width if height > width thenbiggest_dimension = height end_if elsebiggest_dimension = length if height > length thenbiggest_dimension = height end_if end_if
4
Which activity in the fundamental test process includes evaluation of the testability of the requirements and system?
A 'Test Analysis' and 'Design' includes evaluation of the testability of the requirements and system.
What is a V-Model?
A software development model that illustrates how testing activities integrate with software development phases
Explain what it means by test harness?
A test harness is configuring a set of tools and test data to test an application in various conditions, it involves monitoring the output with expected output for correctness.
Explain what is Test Plan ? What are the information that should be covered in Test Plan ?
A test plan can be defined as a document describing the scope, approach, resources and schedule of testing activities and a test plan should cover the following details. Test Strategy Test Objective Exit/Suspension Criteria Resource Planning Test Deliverables
What does a typical test report contains? What are the benefits of test reports?
A test report contains following things: Project Information Test Objective Test Summary Defect The benefits of test reports are: Current status of project and quality of product are informed If required, stake holder and customer can take corrective action A final document helps to decide whether the product is ready for r
Why is incremental integration preferred over "big bang" integration?
Because incremental integration has better early defects screening and isolation ability
What is typically the MOST important reason to use risk to drive testing efforts?
Because testing everything is not feasible.
Why are static testing and dynamic testing described as complementary?
Because they share the aim of identifying defects but differ in the types of defect they find.
A type of integration testing in which software elements, hardware elements, or both are combined all at once into a component or an overall system, rather than in stages.
Big-Bang Testing
What is black box testing? What are the different black box testing techniques?
Black box testing is the software testing method which is used to test the software without knowing the internal structure of code or program. This testing is usually done to check the functionality of an application. The different black box testing techniques are Equivalence Partitioning Boundary value analysis Cause effect graphing
In manual testing what are stubs and drivers?
Both stubs and drivers are part of incremental testing. In incremental testing there are two approaches namely bottom up and top down approach. Drivers are used in bottom up testing and stub is used for top down approach. In order to test the main module, stub is used, whuich is a dummy code or program .
Explain in a testing project what testing activities would you automate?
In a testing project testing activities you would automate are Tests that need to be run for every build of the application Tests that use multiple data for the same set of actions Identical tests that needs to be executed using different browsers Mission critical pages Transaction with pages that do not change in short time
What are the phases of a formal review?
In contrast to informal reviews, formal reviews follow a formal process. A typical formal review process consists of six main steps: Planning Kick-off Preparation Review meeting Rework Follow-up.
In white box testing what do you verify?
In white box testing following steps are verified. Verify the security holes in the code Verify the incomplete or broken paths in the code Verify the flow of structure according to the document specification Verify the expected outputs Verify all conditional loops in the code to check the complete functionality of the application Verify the line by line coding and cover 100% testing
What are the benefits of Independent Testing?
Independent testers are unbiased and identify different defects at the same time.
What are Test comparators?
Is it really a test if you put some inputs into some software, but never look to see whether the software produces the correct result? The essence of testing is to check whether the software produces the correct result, and to do that, we must compare what the software produces to what it should produce. A test comparator helps to automate aspects of that comparision
What is the benefit of test independence?
It avoids author bias in defining effective tests.
When should testing be stopped?
It depends on the risks for the system being tested. There are some criteria bases on which you can stop testing. Deadlines (Testing, Release) Test budget has been depleted Bug rate fall below certain level Test cases completed with certain percentage passed Alpha or beta periods for testing ends Coverage of code, functionality or requirements are met to a specified point
What is the MAIN benefit of designing tests early in the life cycle?
It helps prevent defects from being introduced into the code.
When do we prepare RTM (Requirement traceability matrix), is it before test case designing or after test case designing?
It would be before test case designing. Requirements should already be traceable from Review activities since you should have traceability in the Test Plan already. This question also would depend on the organisation. If the organisations do test after development started then requirements must be already traceable to their source. To make life simpler use a tool to manage requirements
Which of the following tools would be involved in the automation of regression test? a. Data tester b. Boundary tester c. Capture/Playback d. Output comparator.
Output comparator
What is Alpha testing?
Pre-release testing by end user representatives at the developer's site.
What is the KEY difference between preventative and reactive approaches to testing?
Preventative tests are designed early; reactive tests are designed after the software has been produced.
Which of the following are valid objectives for incident reports?
Provide developers and other parties with feedback about the problem to enable identification, isolation and correction as necessary. Provide ideas for test process improvement. Provide a vehicle for assessing tester competence. Provide testers with a means of tracking the quality of the system under test.
What are the categories of debugging?
Categories for debugging a) Brute force debugging b) Backtracking c) Cause elimination d) Program slicing e) Fault tree analysis
What is component testing?
Component testing, also known as unit, module and program testing, searches for defects in, and verifies the functioning of software (e.g. modules, programs, objects, classes, etc.) that are separately testable. Component testing may be done in isolation from the rest of the system depending on the context of the development life cycle and the system. Most often stubs and drivers are used to replace the missing software and simulate the interface between the software components in a simple manner. A stub is called from the software component to be tested; a driver calls a component to be tested.
Consider the following techniques. Which are static and which are dynamic techniques? Equivalence Partitioning. Use Case Testing. Data Flow Analysis. Exploratory Testing. Decision Testing. Inspections.
Data Flow Analysis and Inspections are static; Equivalence Partitioning, Use Case Testing, Exploratory Testing and Decision Testing are dynamic.
What is random/monkey testing? When it is used?
Random testing often known as monkey testing. In such type of testing data is generated randomly often using a tool or automated mechanism. With this randomly generated input the system is tested and results are analysed accordingly. These testing are less reliable; hence it is normally used by the beginners and to see whether the system will hold up under adverse effects.
Rapid Application Development?
Rapid Application Development (RAD) is formally a parallel development of functions and subsequent integration. Components/functions are developed in parallel as if they were mini projects, the developments are time-boxed, delivered, and then assembled into a working prototype. This can very quickly give the customer something to see and use and to provide feedback regarding the delivery and their requirements. Rapid change and development of the product is possible using this methodology. However the product specification will need to be developed for the product at some point, and the project will need to be placed under more formal controls prior to going into production.
During which test activity could faults be found most cost effectively?
During test planning
n a REACTIVE approach to testing when would you expect the bulk of the test design work to be begun?
The bulk of the test design work begun after the software or system has been produced.
What are the common risk that leads to the project failure?
The common risk that leads to a project failure are Not having enough human resource Testing Environment may not be set up properly Limited Budget Time Limitations
As part of which test process do you determine the exit criteria?
The exit criteria is determined on the bases of 'Test Planning'.
What determines the level of risk?
The likelihood of an adverse event and the impact of the event determine the level of risk.
In which order should tests be run?
The most important one must tests first
Explain how to test documents in a project that span across the software development lifecycle?
The project span across the software development lifecycle in following manner Central/Project test plan: It is the main test plan that outlines the complete test strategy of the project. This plan is used till the end of the software development lifecycle Acceptance test plan: This document begins during the requirement phase and is completed at final delivery System test plan: This plan starts during the design plan and proceeds until the end of the project Integration and Unit test plan: Both these test plans start during the execution phase and last until the final delivery
What is the purpose of exit criteria?
The purpose of exit criteria is to define when a test level is completed.
What is traceability matrix?
The relationship between test cases and requirements is shown with the help of a document.
Explain what is N+1 testing?
The variation of regression testing is represented as N+1. In this technique the testing is performed in multiple cycles in which errors found in test cycle 'N' are resolved and re-tested in test cycle N+1. The cycle is repeated unless there are no errors found.
What are the different Methodologies in Agile Development Model?
There are currently seven different agile methodologies that I am aware of: Extreme Programming (XP) Scrum Lean Software Development Feature-Driven Development Agile Unified Process Crystal Dynamic Systems Development Model (DSDM)
What are different test levels?
There are four test levels Unit/component/program/module testing Integration testing System testing Acceptance testing
Why we split testing into distinct stages?
We split testing into distinct stages because of following reasons, Each test stage has a different purpose It is easier to manage testing in stages We can run different test into different environments Performance and quality of the testing is improved using phased testing
What is DFD (Data Flow Diagram) ?
When a "flow of data" through an information system is graphically represented then it is known as Data Flow Diagram. It is also used for the visualization of data processing.
What is fault masking explain with example?
When presence of one defect hides the presence of another defect in the system is known as fault masking. Example : If the "Negative Value" cause a firing of unhandled system exception, the developer will prevent the negative values inpu. This will resolve the issue and hide the defect of unhandled exception firing.
What is white box testing and list the types of white box testing?
White box testing technique involves selection of test cases based on an analysis of the internal structure (Code coverage, branches coverage, paths coverage, condition coverage etc.) of a component or system. It is also known as Code-Based testing or Structural testing. Different types of white box testing are Statement Coverage Decision Coverage
What are the Structure-based (white-box) testing techniques?
Structure-based testing techniques (which are also dynamic rather than static) use the internal structure of the software to derive test cases. They are commonly called 'white-box' or 'glass-box' techniques (implying you can see into the system) since they require knowledge of how the software is implemented, that is, how it works. For example, a structural technique may be concerned with exercising loops in the software. Different test cases may be derived to exercise the loop once, twice, and many times. This may be done regardless of the functionality of the software.
What is Boundary value testing?
Test boundary conditions on, below and above the edges of input and output equivalence classes. For instance, let say a bank application where you can withdraw maximum Rs.20,000 and a minimum of Rs.100, so in boundary value testing we test only the exact boundaries, rather than hitting in the middle. That means we test above the maximum limit and below the minimum limit.
Which of the following defines the expected results of a test? Test case specification or test design specification.
Test case specification defines the expected results of a test.
What are the tables in testplans?
Test design, scope, test strategies , approach are various details that Test plan document consists of. Test case identifier Scope Features to be tested Features not to be tested Test strategy & Test approach Test deliverables Responsibilities Staffing and training Risk and Contingencies
What is beta testing?
Testing performed by potential customers at their own locations.
What is functional system testing?
Testing the end to end functionality of the system as a whole is defined as a functional system testing.
What are the best practices for software quality assurance?
The best practices for an effective SQA implementation is Continuous Improvement Documentation Tool Usage Metrics Responsibility by team members Experienced SQA auditors
We use the output of the requirement analysis, the requirement specification as the input for writing ...
User Acceptance Test Cases
"This life cycle model is basically driven by schedule and budget risks" This statement is best suited for...
V-Model
In practice, which Life Cycle model may have more, fewer or different levels of development and testing, depending on the project and the software product. For example, there may be component integration testing after component testing, and system integration testing after system testing.
V-Model
What is verification and validation?
Verification is a process of evaluating software at development phase and to decide whether the product of a given application satisfies the specified requirements. Validation is the process of evaluating software at the end of the development process and to check whether it meets the customer requirements.
When is used Decision table testing?
Decision table testing is used for testing systems for which the specification takes the form of rules or cause-effect combinations. In a decision table the inputs are listed in a column, with the outputs in the same column but below the inputs. The remainder of the table explores combinations of inputs to define the outputs produced.
what are the different types of test coverage techniques?
Different types of test coverage techniques include Statement Coverage: It verifies that each line of source code has been executed and tested Decision Coverage: It ensures that every decision in the source code is executed and tested Path Coverage: It ensures that every possible route through a given part of code is executed and tested
what is the purpose behind doing end-to-end testing?
End-to end testing is done after functional testing. The purpose behind doing end-to-end testing is that To validate the software requirements and integration with external interfaces Testing application in real world environment scenario Testing of interaction between application and database
What is Equivalence partitioning testing?
Equivalence partitioning testing is a software testing technique which divides the application input test data into each partition at least once of equivalent data from which test cases can be derived. By this testing method it reduces the time required for software testing.
What is a failure?
Failure is a departure from specified behaviour.
How will you conduct Risk Analysis?
For the risk analysis following steps need to be implemented a) Finding the score of the risk b) Making a profile for the risk c) Changing the risk properties d) Deploy the resources of that test risk e) Making a database of risk
What is Fuzz testing and when it is used?
Fuzz testing is used to detect security loopholes and coding errors in software. In this technique random data is added to the system in attempt to crash the system. If vulnerability persists, a tool called fuzz tester is used to determine potential causes. This technique is more useful for bigger projects but only detects major fault.
What type of review requires formal entry and exit criteria, including metrics?
Inspection
What is Integration Testing?
Integration Testing is the process of testing the interface between the two software units. Integration testing is done by three ways. Big Bang Approach, Top Down Approach, Bottom-Up Approach
What is Integration testing?
Integration testing is a level of software testing process, where individual units of an application are combined and tested. It is usually performed after unit and functional testing.
What are the common mistakes which creates issues ?
Matching resources to wrong projects Test manager lack of skills Not listening to others Poor Scheduling Underestimating Ignoring the small problems Not following the process
How would you estimate the amount of re-testing likely to be required?
Metrics from previous similar projects and discussions with the development team
What is the difference between re-testing and regression testing?
Re-testing ensures the original fault has been removed; regression testing looks for unexpected side effects.
What are the valuable steps to resolve issues while testing?
Record : Log and handle any problems which has happened Report: Report the issues to higher level manager Control: Define the issue management process
Which of the following is likely to benefit most from the use of test tools providing test capture and replay facilities? a) Regression testing b) Integration testing c) System testing d) User acceptance testing
Regression testing
what is Regression Testing ?
Repeated Testing of an already tested program, after modification, to discover any defects introduced or uncovered as a result of the changes in the software being tested or in another related or unrelated software component:
Mention the difference between Data Driven Testing and Retesting?
Retesting: It is a process of checking bugs that are actioned by development team to verify that they are actually fixed. Data Driven Testing (DDT): In data driven testing process, application is tested with multiple test data. Application is tested with different set of values.
What is risk-based testing?
Risk-based Testing is the term used for an approach to creating a Test Strategy that is based on prioritizing tests by risk. The basis of the approach is a detailed risk analysis and prioritizing of risks by risk level. Tests to address each risk are then specified, starting with the highest risk first.
What is the difference between STLC (Software Testing Life Cycle) and SDLC (Software Development Life Cycle) ?
SDLC deals with developement/coding of the software while STLC deales with validation and verification of the software
During the testing of a module tester 'X' finds a bug and assigned it to developer. But developer rejects the same, saying that it's not a bug. What 'X' should do?
Send to the detailed information of the bug encountered and check the reproducibility
What is the difference between static and dynamic testing?
Static testing: During Static testing method, the code is not executed and it is performed using the software documentation. Dynamic testing: To perform this testing the code is required to be in an executable form.
What is the difference between UAT (User Acceptance Testing) and System testing?
System Testing: System testing is finding defects when the system under goes testing as a whole, it is also known as end to end testing. In such type of testing, the application undergoes from beginning till the end. UAT: User Acceptance Testing (UAT) involves running a product through a series of specific tests which determines whether the product will meet the needs of its users.
What all things you should consider before selecting automation tools for the AUT?
Technical Feasibility Complexity level Application stability Test data Application size Re-usability of automated scripts Execution across environment
Explain what is Test Deliverables ?
Test Deliverables are set of documents, tools and other components that has to be developed and maintained in support of testing. There are different test deliverables at every phase of the software development lifecycle Before Testing During Testing After the Testing
What is difference between Test matrix and Traceability matrix?
Test Matrix: Test matrix is used to capture actual quality, effort, the plan, resources and time required to capture all phases of software testing Traceability Matrix:Mapping between test cases and customer requirements is known as Traceability Matrix
List out Test Deliverables?
Test Strategy Test Plan Effort Estimation Report Test Scenarios Test Cases/Scripts Test Data Requirement Traceability Matrix (RTM) Defect Report/Bug Report Test Execution Report Graphs and Metrics Test summary report Test incident report Test closure report Release Note Installation/configuration guide User guide Test status report Weekly status report (Project manager to client)
Explain what is "Test Plan Driven" or "Key Word Driven" method of testing?
This technique uses the actual test case document developed by testers using a spread sheet containing special "key Words". The key words control the processing.
How you can eliminate the product risk in your project ?
To eliminate product risk in your project, there is simple yet crucial step that can reduce the product risk in your project. Investigate the specification documents Have discussions about the project with all stakeholders including the developer As a real user walk around the website
On what basis you can arrive to an estimation for your project?
To estimate your project , you have to consider following points Divide the whole project into a smallest tasks Allocate each task to team members Estimate the effort required to complete each task Validate the estimation
The purpose of requirement phase is
To freeze requirements, to understand user needs, to define the scope of testing
Explain what is testing type and what are the commonly used testing type ?
To get an expected test outcome a standard procedure is followed which is referred as Testing Type. Commonly used testing types are Unit Testing: Test the smallest code of an application API Testing: Testing API created for the application Integration Testing: Individual software modules are combined and tested System Testing: Complete testing of system Install/UnInstall Testing: Testing done from the point of client/customer view Agile Testing: Testing through Agile technique
What is the MAIN objective when reviewing a software deliverable?
To identify defects in any software work product.
What are the two parameters which can be useful to know the quality of test execution?
To know the quality of test execution we can use two parameters Defect reject ratio Defect leakage ratio
What is DRE?
To measure test effectiveness a powerful metric is used to measure test effectiveness known as DRE (Defect Removal Efficiency) From this metric we would know how many bugs we have found from the set of test cases. Formula for calculating DRE is DRE=Number of bugs while testing / number of bugs while testing + number of bugs found by user
To test a function, what has to write a programmer, which calls the function to be tested and passes it test data.
driver
