Best Practices for Using Synthetic Test Data in Software Development and Testing


Jan Kellner, Consultant at Automators

10 min readJul 17 2023


Best practices for using synthetic test data in software development and testing

In the world of software development and testing, the use of test data is crucial in ensuring the reliability and functionality of software systems. Test data serves as the foundation for simulating real-world scenarios, validating software behavior, and uncovering potential issues. While real data can be valuable, it may not always be easily available or suitable for testing purposes. That’s where synthetic (or fake) test data comes in.

Synthetic test data is data that has been manufactured artificially in order to simulate real-world scenarios and conditions. Unlike real data, which is derived from actual users or systems, synthetic test data is created programmatically or throughdata generation tools. This data closely resembles the characteristics and attributes of real data, giving it an excellent option for thorough testing without the risks associated with using actual sensitive or private information.

There are several reasons why it is crucial to use thetest data in software development and testing. Firstly, it allows developers and testers to evaluate how the software performs under various conditions, identify bugs or vulnerabilities, and ensure that it meets the desired requirements. Test data also enables the validation of system behavior across various scenarios and edge cases, which ensures robustness and reliability.

Additionally, test data helps to measure the performance and scalability of the software, ensuring that it can manage varied workloads and user interactions. It also assists in the detection and correction of potential data-related issues, such as data corruption, data loss, or discrepancies. By incorporating test data into the development and testing process, teams may enhance the overall quality and performance of their software.

In this blogpost we will describe the best practices for effectively utilizing synthetic test data in software development and testing, which make it more reliable and efficient.


1. Choosing the Right Data Generation Approach

To effectively utilize synthetic test data, it is crucial to select the appropriate data generation approach that corresponds with the testing process´s requirements and objectives. Before deciding on a data generating strategy, it is essential to have a clear understanding of the testing requirements and objectives. This involves identifying the specific scenarios, use cases, and data variations that need to be covered by the synthetic test data. Defining the testing objectives helps to reduce the options and choose an approach that best suits specific demands.

There are various data generation techniques available, each with its own strengths and limitations. We have described in detail rule-based and model-based approaches in this blogpost(Comparison of model based generation versus rule based generation). Teams can make an informed decision on the most appropriate approach for their testing needs by evaluating these techniques and considering their advantages and limitations.


2. Designing Relevant Test Scenarios

To effectively use synthetic test data in software development and testing, relevant test scenarios must be designed. Following are the key steps to take:

Identifying key use cases and user personas: Start by identifying the key use cases and user personas that the software aims to serve. Understanding the target audience, their goals, and the specific interactions they will have with the software are all parts of that. By identifying these use cases and user personas, you can create test scenarios that closely resemble real-world usage patterns.

Defining realistic data variations and combinations: Once the use cases and user personas are identified, it’s important to define realistic data variations and combinations that correspond with those scenarios. Consider the different attributes, characteristics, and parameters that can vary within each use case. Factors such as user demographics, input data, environment settings, or system configurations should be included. By incorporating these variations into the synthetic test data, you can assure complete coverage of different scenarios.

Incorporating edge cases and abnormal situations: It is crucial to incorporate edge cases and abnormal scenarios into your test scenarios in addition to covering typical use cases. These are situations that test the software´s ability to handle unexpected inputs or conditions. By including those edge cases and abnormal scenarios, it is possible to identify potential vulnerabilities or performance issues and ensure the software’s resilience.

Linking test scenarios to specific test objectives: Each test scenario should be linked to a specific test objective. Define exactly what you aim to validate or verify with each scenario. This might involve functionality testing, performance testing, security testing, or any other specific aspect of the software that needs to be evaluated. By linking the scenarios to test objectives, you can ensure that the synthetic test data is aligned with your testing goals and that the results are relevant and actionable.

By following these steps and designing relevant test scenarios, you can create synthetic test data that accurately reflects real-world usage patterns, covers a wide range of scenarios, and helps you achieve comprehensive testing coverage.


3.Ensuring Data Quality and Consistency

The following are the key practices to ensure the effectiveness of synthetic test data in software development and testing:

Establish robust data validation and verification processes to ensure the quality and integrity of synthetic test data. This involves defining validation rules and checks to verify that the generated data is correct, complete, and consistent. Implement automated validation mechanisms to detect and handle any anomalies or errors in the synthetic test data.

Implement data quality checks into the data generation and utilization processes. This includes identifying and rectifying any discrepancies, outliers, or invalid data points. Define error handling mechanisms to manage any errors or exceptions that may arise during the generation or usage of synthetic test data. By ensuring data quality, you can rely on the accuracy and reliability of the test results.

Consider the dependencies and relationships within the synthetic test data. Ensure that data dependencies are effectively managed and that data entity relationships are represented appropriately. This includes maintaining referential integrity and consistency across related data elements. Proper management of data dependencies and relationships is crucial for realistic and relevant test scenarios.

Synthetic test data should not be considered as a one-time effort. It requires regular updates and maintenance to stay relevant and effective. As the software evolves, it is essential to update the synthetic test data to reflect changes in requirements, features, and data formats. Review and update the test scenarios regularly to meet new use cases and edge situations. By updating and maintaining the synthetic test data on a regular basis, you can ensure the continuing usefulness and applicability throughout the software development and testing lifecycle.

Implementing these practices to ensure data quality and consistency allows you to rely on the synthetic test data to accurately represent real-world scenarios, uncover potential issues, and provide valuable insights into the performance and functionality of the software.


4. Incorporating Data Diversity

To enhance the effectiveness of synthetic test data, it is important to incorporate data diversity. This involves reflecting diverse user demographics and behaviors, incorporating various data formats and sources, and utilizing data augmentation techniques. Here are the key practices to follow:

Ensure that the synthetic test data represents a diverse range of user demographics and behaviors. When creating test data, consider factors such as age, gender, location, and occupation. By incorporating diversity, you can identify potential issues that may arise for different user segments and ensure that the software can be used by a wide range of users.

To accurately simulate real-world scenarios, incorporate** various data formats and sources** into your synthetic test data. This could include structured data, unstructured data, multimedia files, or real-time data streams. You can test the software’s ability to handle a variety of data inputs and ensure compatibility with different data types when using different data formats and sources.

You can effectively evaluate how the software performs across different user groups, data formats, and scenarios by incorporating data diversity into your synthetic test data. This helps in identifying potential biases, uncovering edge cases, and ensuring that the software is robust and inclusive.


5. Ensuring Data Relevance and Adaptability

To maximize the effectiveness of synthetic test data, it is important to ensure its relevance and adaptability. Here are some of the key practices that are good to be followed:

Periodically review the relevance of the synthetic test data to ensure it matches with the evolving requirements and objectives of the testing process. As the software evolves, new features are added, or user expectations change, it is crucial to determinate whether the existing test data adequately covers the updated scenarios. Identify any gaps or areas where the synthetic test data may be outdated or insufficient, and plan for updates accordingly.

Gather feedback from testers and end users regarding the effectiveness and realism of the synthetic test data. This can be done through surveys, interviews, or feedback sessions. Understand their experiences, identify any areas for improvement, and capture new use cases or edge cases that may have been missed initially. You can enhance the relevance and accuracy of the synthetic test data by incorporating feedback to better reflect real-world scenarios and user behaviors.

Adapt and update the synthetic test data when requirements change, or new scenarios occur. This might include adding new data points, modifying existing data variations, or introducing new data sources. By keeping the synthetic test data up to date and aligned with the changing requirements, you can ensure that it stays relevant and effective throughout the software development and testing process.

Collaborate closely with developers and testers to effectively exploit the synthetic test data. Participate in discussions and exchange suggestions on how to improve test data to address specific testing objectives or issues. By involving developers and testers in the process, you can leverage their expertise to enhance the adaptability and effectiveness of the synthetic test data.

By regularly assessing relevancy, incorporating feedback, adapting to changing requirements, and collaborating with stakeholders, you can ensure that the synthetic test data remains relevant, accurate, and adaptable. This contributes to more effective testing and improves the software’s quality and reliability.


6. Integrating Synthetic Test Data into Testing Processes

To effectively integrate synthetic test data into testing processes, follow these best practices to maximize its value and contribute to more efficient and effective software testing.

Defining the right test coverage for synthetic test data: Identify the areas of the software that require coverage using synthetic test data. Determine which test scenarios and use cases will benefit most from including synthetic test data. By defining the right test coverage, you can ensure that synthetic test data is utilized where it provides the most value and helps achieve testing objectives.

Implement automation processes for generating and utilizing synthetic test data. This involves developing scripts or tools that can automatically generate synthetic test data based on predefined rules or specifications. One of such tools is our Datamaker.Additionally, automate the integration of synthetic test data into test cases to make it smoother and more efficient. Automation simplifies the testing process and enables repeated use of synthetic test data as needed.

Integrate synthetic test data seamlessly with existing testing tools and frameworks. This ensures that the synthetic test data can be easily incorporated into the testing workflow without requiring significant changes to the existing infrastructure. Integration may involve developing adapters or plugins to enable the use of synthetic test data with tools such as test management systems, test automation frameworks, or continuous integration/continuous delivery pipelines.

Final Thoughts

In conclusion, adopting best practices in synthetic data testing is a pivotal step towards ensuring the efficiency and accuracy of software testing processes. By harnessing the power of synthetic data generation methods, organizations can overcome challenges associated with sensitive or limited test data, reduce data management overhead, and enhance the reproducibility of test scenarios. Employing these best practices not only accelerates the testing lifecycle but also facilitates comprehensive test coverage, ultimately leading to higher software quality and more robust applications. As software systems grow in complexity, the integration of synthetic data testing becomes increasingly crucial in maintaining the reliability and security of the software, making it a valuable asset for modern development and quality assurance efforts. Tools like Datamaker can greatly streamline this process, empowering your organization to harness the full potential of synthetic data for superior testing outcomes.

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