What is Test Data

What is Test Data

What is Test Data in Software Testing?

Test Data in Software Testing is the input given to a software program during test execution. It represents data that affects or is affected by software execution while testing. Test data is used for positive testing to verify that functions produce expected results for given inputs and for negative testing to test software’s ability to handle unusual, exceptional, or unexpected inputs.
Poorly designed testing data may only test some possible test scenarios, which will hamper the quality of the software.
What is Test Data Generation? Why should test data be created before test execution?
Everybody knows that testing is a process that produces and consumes large amounts of data. Data used in testing describes the initial conditions for a test and represents the medium through which the tester influences the software. It is a crucial part of most Functional tests.

Depending on your testing environment, you may need to CREATE Test Data (Most of the time) or identify suitable test data for your test cases (if the test data is already created).

Test Data can be Generated:


Mass copy of data from production to testing environment

Mass copy of test data from legacy client systems

Automated Test Data Generation Tools

Typically, sample data should be generated before you begin test execution because it is challenging to handle test data management otherwise. In many testing environments, creating test data takes multiple pre-steps or very time-consuming test environment configurations. Also, If test data generation is done while you are in the test execution phase, you may exceed your testing deadline.

Below are described several testing types and suggestions regarding their testing data needs.

Test Data for White Box Testing:

In White Box Testing, test data Management is derived from directly examining the code to be tested. Test data may be selected by taking into account the following things:

It is desirable to cover as many branches as possible; testing data can be generated such that all branches in the program source code are tested at least once

Path testing: all paths in the program source code are tested at least once – test data preparation can be done to cover as many cases as possible

Negative API Testing:

Testing data may contain invalid parameter types used to call different methods.
Testing data may consist of invalid combinations of arguments that are used to call the program’s methods.

Test Data for Performance Testing

Performance Testing is the type of testing performed to determine how fast the system responds under a particular workload. The aim of this type of testing is not to find bugs but to eliminate bottlenecks. An essential aspect of Performance Testing is that the set of sample data used must be very close to ‘real’ or ‘live’ data that is used in production. The following question arises: ‘Okay, it’s good to test with real data, but how do I obtain it?’ The answer is straightforward: from the people who know the best – the customers. They may be able to provide some data they already have, or if they don’t have an existing set of data, they may help you by giving feedback regarding how the real-world data might look. If you are in a maintenance testing project, you could copy data from the production environment into the testing bed. It is an excellent practice to anonymize (scramble) sensitive customer data like Social Security Numbers, Credit Card Numbers, Bank Details, etc., while the copy is made.

Test Data for Security Testing

Security Test is the process that determines if an information system protects data from malicious intent. The set of data that needs to be designed to test software security fully must cover the following topics:

Confidentiality: All the information clients provide is held strictly confidential and is not shared with any outside parties.

Integrity: Determine that the information provided by the system is correct. To design suitable test data, you can look in-depth at the design, code, databases, and file structures.

Authentication: Represents the process of establishing the identity of a user. Testing data can be designed as a different combination of usernames and passwords, and its purpose is to check that only authorized people can access the software system.

Authorization: Tells what are the rights of a specific user. Testing data may contain a different combination of users, roles, and operations to check only users with sufficient privileges can perform a particular operation.

Test Data for Black Box Testing

In Black Box Testing, the code is not visible to the tester. Your functional test cases can have test data meeting the following criteria –

No data: Check system response when no data is submitted
Valid data: Check system response when Valid test data is submitted
Invalid data: Check system response when InValid test data is submitted
Illegal data format: Check system response when test data is in an invalid format
Boundary Condition Dataset: Test data meeting boundary value conditions
Equivalence Partition Data Set: Test data qualifying your equivalence partitions.
Decision Table Data Set: Test data qualifying your decision table testing strategy
State Transition Test Data Set: Test data meeting your state transition testing strategy
Use Case Test Data: Test Data in sync with your use cases.

Automated Test Data Generation Tools

To generate various data sets, you can use a gamut of automated test data generation tools. Below are some examples of such tools:
DTM Test Data Generator is a fully customizable utility that generates data and tables (views, procedures, etc) for database testing (performance testing, QA testing, load testing, or usability testing) purposes.
Datatect is a SQL data generator by Banner Software that generates a variety of realistic test data in ASCII flat files or directly generates test data for RDBMS, including Oracle, Sybase, SQL Server, and Informix.


In conclusion, well-designed testing data allows you to identify and correct severe flaws in functionality. The choice of test data must be reevaluated in every phase of a multi-phase product development cycle. So, always keep an eye on it. To facilitate this process, using an efficient test data generation tool could significantly streamline your workflow.