Backend Testing Guide

On May 13, 2022
7min read
Grigori Monaselidze Content Manager @ Mailtrap

Backend Testing allows the software to achieve high performance and maintenance. With complicated and intricate databases, mastering Backend Testing requires proper automated functionality, giving your users a satisfactory experience.

Backend Testing helps the developers secure correct communication between interdependent and interconnected components on the server-side of the application. With a confirmed automated functionality, the data production and storage will maintain proper functionality – yielding beneficial results on all sides of the application. 

What is Backend Testing?

Backend Testing verifies the functionality of software’s or application’s serverside and database. This testing method makes sure that all server-side components have proper intercommunication and cooperation without any defects.

A standard application consists of the front and back end. Backend Testing elements are invisible to the users, yet most work occurs there. QA Team during Backend Testing also conducts API Testing and Database Testing.

Database Testing ensures proper functionality of all data-related components on the server-side of the application. Meaning the front end will store all newly acquired data in the back end database, which may be SQL or non-SQL. This data is recorded and stored to support the frontend components of the page.

Properly performed backend or database testing is essential to eliminate any serious complications. These could be deadlocks, data corruption or losses that are harmful to softwares and applications.

Additionally, Backend Testing is the go-to method to accelerate the productivity and retention of software or applications. With proper Backend Testing, you will be able to:

  • Have a thorough test of your application and control over its coverage;
  • Discover defects, and resolve them before escalation;
  • Avoid data corruptions or losses, alongside deadlocks;
  • Improve system functionality and stability;
  • Improve data quality and integrity;

Since Backend Testing does not require interaction with the frontend, sending and receiving requests and answers is a simpler process. You can pass the request through a browser with specific parameters for a specific function. This will result in a response in a default format, JSON or XML, for example. Additionally, you will be able to verify the data with SQL queries via database connection and conduct any debugging through the log files.

Backend Testing involves various phases. Beginning with design specification acquisition for the database server, followed by testing of the specification design and implementation of the tests in the design via SQL.

Backend Testing Types

To effectively conduct Backend Testing, it is important to understand the business requirements and build effective testing strategies. As it is performed on the database layer of any software or application, Backend Testing is essential before any launch. There are three types of Backend Testing:

  • Structural Testing − This deals with table and column testing, schema testing, stored procedures and views testing, checking triggers, etc.
  • Functional Testing − This involves checking the functionality of the database from the user’s point of view. The most common type of Functional testing is a white box and black box testing.
  • Non-functional Testing − This involves load-testing, risk testing in the database, stress testing, minimum system requirements, and deals with the performance of the database.

Structural Testing

Structural Database Testing requires mastery of SQL queries. It tests the table and column, alongside the schema of the database, validating the integrity and storage of all data repository components. This validation is important in structural database testing.

Schema Testing

Schema Testing, also referred to as Mapping Testing, validates various schematic formats associated with the database. This testing method verifies if the mapping formats of all backend components are compatible with the ones on the frontend. The main purpose is to ensure stability and similarity between the front and back end maps.

Functional Testing

Functional Testing method validates the transactional and operational functionality from the frontend perspective. Specifically, functionality related to the database. These conditions are primary observation objectives during Functional Testing:

  • Is the length of each field sufficient?
  • Is a specific field needed while allowing null values?
  • Do all similar fields have similar names across the tables?
  • Are there any computed fields present?

After verifying the functionality of these conditions, the tester should refer to the front end and observe and validate it from the interface. If an issue is detected, the tester returns to the back end, resolves it, and returns back to the front for functionality verification.

Non-functional Testing

Non-functional Testing is a series of different testing methods, depending on the business requirements. It includes Performance Testing (which includes Stress and Load Testing), Security Testing, Usability Testing, Compatibility Testing and more. 

Risk Qualification is a part of Non-functional Testing. It allows QA team to access various response rates of the system under several levels of pressure. Risk Qualification presents corrective opportunities for risk mitigation, such as risk identification and risk qualification. This is an essential stage of any Quality Assurance process. This process also identifies the minimum system equipment requirements.

Performance Testing

Performance Testing evaluates the responsiveness, performance and stability of the system under various levels of pressure. When conducting this examination, mind the following components:

  • Network and browser response time
  • Processor memory consumption
  • Server query process time
  • User Volume stability

Performance Testing, including Stress & Load Testing, examines the overall performance of the software. Also, it determines the software’s stability, reliability, speed, and strength. 

Security Testing

Security Testing identifies threats and risks present in the software which could have a detrimental impact on the business. These vulnerabilities might result in a loss of information or revenue, alongside increasing the possibility of intrusion. 

Open Source Security Testing methodology manual explains seven main types of Security Testing:

  • Vulnerability Scanning
  • Security Scanning
  • Penetration testing
  • Risk Assessment
  • Security Auditing
  • Ethical Hacking
  • Posture Assessment 

Security Testing’s objective is to locate all malfunctions and vulnerabilities threatening your employees’ and customers’ security.

Usability Testing

Usability Testing observes users’ navigation of the interface, ensuring the design’s accessibility. Usually conducted repeatedly, Usability Testing aims to improve the usability of the interface through design improvements. This testing is mainly useful to identify whether users are able to successfully and optimally complete a specified task. This provides insight into the satisfaction and performance of the users, which helps identify the improvement opportunities.

Usability Testing can be done both physically and remotely. The main difference between the two options is a moderator. In a physical setting, a moderator observes the condition better, yet also guides the user to a specific objective. A remote setting, however, reveals a more realistic experience. Mainly, there are several aims to consider during Usability Testing:

  • How successfully, optimally, and independently was the task completed;
  • How satisfied were the users with the navigation to their destination;
  • What were the design improvement points during the performance.

Compatibility Testing

Compatibility Test verifies the functionality of the software across various internet browsers, operating systems, mobile devices, databases, networks, and hardwares. These tests are crucial to ensure the successful performance of the software. There are two types of Compatibility Testing: Backward Compatibility Testing & Forward Compatibility Testing. 

Backward Compatibility Testing

Backward, or Downward Compatibility Testing verifies the successful performance of older versions of the software on newer operating systems and devices. 

Forward Compatibility Testing

Forward Compatibility Testing verifies the successful performance of the software on the newer versions of operating systems and devices. 

How to do Backend Testing

The previous section explored all of the aspects of Backend Testing elements. With Backend Testing, you mainly need to validate the entire server’s performance and function, alongside its cooperation with the interface. It includes focusing on the success of schematics, columns, keys, indexes, database tables, stored procedures, and identifying triggers and issues.

Before the compound procedure of Backend Testing, begin the process by acquiring the server design. Those steps test the functionality of the set design and identify its improvements with SQL code.

Backend Testing does not require interference with the GUI. Tester mainly passes the requests through browser with specific parameters in either XM or JSON format. This allows the identification of a feature’s success or failure. The testing also requires a direct connection with the database to verify the data using SQL queries through log files. 

Even though Backend Testing does not require interference with the frontend, Frontend Testing is an inseparable part of a successfully tested software.

Frontend Testing & Backend Testing: Difference?

In 3 Tier Architecture, Frontend Testing assesses the Presentation Layer of the application, while Backend Testing – Application & Database Layer. 

The functionality of all GUI components is verified by Frontend Testing; functionalities of forms, graphs, menus, reports and the associated code. Similar to Backend Testing, Frontend Testing includes a variety of testing methods. 

The main difference between Frontend Testing & Backend Testing is the 3 Tier Architecture Layer where the testing is conducted. Here are the core differences between them:

Frontend TestingBackend Testing
Performed on the GUIPerformed in the Server & Database
Does not require database interventionRequires database intervention
Requires interface interventionMay require interface intervention
Verifies the overall functionalityVerifies security & stability

Tools for Backend Testing

Both Backend have a large variety of useful tools. These tools used for Database Testing allow improved performance by locating potential issues, such as deadlocking, data corruption, and data loss.

  • Data Factory generates a layer for digital transformation initiatives. A user-friendly interface allows for simpler data management.
  • Data Generator is the main tool used during Performance Testing. It generates data columns and schema objects.

Tools for Backend Automation Testing

Compared to manual, automated testing is the most innovative software testing method. Backend Automation Testing tools could simplify the testing process in a time-efficient and cost-effective manner. Some of these tools are open-source, offering a lot of functionalities and integrations. 

  • Testim is considered the best tool for scalability. Testim Automate uses AI to locate the visual elements and increase the stability of UI functionality during testing.
  • Postman includes various essential request methods and tools for efficient API testing.
  • SOAP UI is a leading Functional Testing tool for SOAP and REST testing.
  • Browserstack is for automation testing on actual mobile devices and internet browsers.
  • Kobiton is a cloud-based platform for simultaneously accessing and running manual and automated tests on various devices.
  • JMeter is a tool for Load Testing to analyze and measure the performance of the software.
  • Mabl is best for executing and maintaining low-code automated API tests.
  • Testrigor is for no-code scalability and end-to-end automation tests.
  • Telerik is a cost-efficient automated test execution platform with a built-in code editor.

These tools are merely some of the many available on the market. They will help your QA team conduct successful Automated Backend Tests. This testing method is a revolutionary solution to improved Backend Testing.

Backend Testing & Email Infrastructure

Testing your email infrastructure is another important aspect of Backend Testing. As it verifies the entire functionality of your service, the communication between the business and the clients occurs through an email. Successful email deliverability ensures stable retention and customer satisfaction.

With Email Infrastructure, you must verify the successful delivery of your transactional emails. During Backend Testing, communication between your email sending solution and application database must be verified. This ensures the stable exchange of data during necessary automated sending procedures.

Aside from that, your emails must be tested in various aspects to achieve success, such as spam score and design. The overall testing procedure could be dangerous if not done on a secure server, avoiding accidental sending to any customer.

Mailtrap is a testing and sending solution that covers all of that. Mailtrap provides a comprehensive toolbox with a dummy SMTP server to catch and verify your emails during staging safely.

1. Sign up in under a minute.

2. Get the credentials for your application.

3. Check and validate your HTML layout, email spam score and even Load Test your application by sending a high volume of emails.


Backend Testing is essential for properly-functioning software and application, alongside increasing client retention. Therefore, testing all of your outgoing emails can greatly benefit retention. This can be possible through various reports, such as spam scores and HTML checks provided in the app itself.

And even though Backend Testing may increase the cost of QA, it ensures stability and security for your customers. A strong team of testers, undertaking a large variety of testing processes, can make a significant difference to your business.

There is a large number of applications available on the market, however, the ones with the most stability and security, alongside determination for customer-oriented progression, stand out.

Identify the objectives of your business and fully utilize Backend Testing to ensure customer satisfaction and retention, alongside overall success.

Article by Grigori Monaselidze Content Manager @ Mailtrap