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Database Testing – An introduction

A database plays a vital role in any organization as a storage facility for useful data. Every developed software application needs data to being stored but measures need to be in place to make sure that only information that is relevant and useful will be retained.

To do this, database testing is carried out on many levels including checking for duplicate data, data integrity, and checking data validity by means of check constraints. The purpose of database testing is to identify defects which are not usually found through routine functional testing.

Significance of Database Testing

Validated stored data against specified requirements is referred to as database testing. When data is entered in a UI screen by the user, it should match the record stored in the database. Modern application development is becoming increasingly intricate, so testing across all levels is highly necessary. In order to deliver applications that are reliable and robust, database testing must be performed so that any loopholes in the system can be found and rectified. Databases can be complex setups, depending on the business logic behind their design and built. However, we must ensure that whatever the design, all values can be added correctly into the system. Moreover, we need to carry out routine testing to confirm expected outcomes in areas such as addition, updating, and deleting, to check the stability of the database. The aim of every test session is to discover defects and to correct them. Database testing is critical to good database performance and hence requires proficiency in writing queries and procedures.

There are many aspects of database testing which we can include in our testing process.

Data Mapping

We expect to find that data is present in the database concerning every application. We should be able to retrieve requested data from the database whenever it is needed. To make sure this is possible, testers have to make sure that:

  • The user interface must map with the related fields in the database table and there should be no inconsistencies between them.
  • Whenever an action is performed in the front-end, corresponding CRUD (Created, Retrieve, Update, and Delete) operation must invoke at the back-end.

Validating ACID

Each transaction that is carried out in the database must comply with the acronym, ACID, which means Atomicity, Consistency, Isolation, and Durability. In order to validate these properties, testers have to create suitable test cases for each transaction.

Data Integrity

Data integrity means the assurance of data accuracy within the database. Any value stored in the database, must not show any signs of change or corruption. Specific test cases must be created to validate data integrity and maintain consistency.

Business Logic

Applications have complex data within them. To conform to the business logic of the application, components such as triggers, constraints, stored procedures, etc. need to be checked for precision. To be able to perform such validation, testers should be well-versed in writing complex queries.

Database testing

Types of Database Testing

Black Box Testing

In black box testing, the focus is on the input and output of the application, not the implementation details. However, the tester should have knowledge of database design. In the database, this includes:

  • Verifying the data being input by the user and the output result
  • Verification of data with the use of query language

White Box Testing

In white box testing concerns the implementation of the application. The tester should know about the implementation details so that defects can be identified. In the database, this includes:

  • Verification of triggers, views etc.
  • Verification of functions, and stored procedures
  • Checking tables, models, schemas etc.
  • Checking integrity constraints

Challenges and Limitations

Abnormally Large Scope

Before starting a very large database test, identify the particular items to be tested, then work out an estimate of the time needed for creating the test cases and their execution. Once you have a time framework, testing can be executed in an effective manner which will contribute towards the quality of the system. If you have a strict deadline, prioritize the important items to make sure they can be performed within the schedule.

Modification of Schema

Modification the schema of a database can be quite a challenge because, despite meticulous checking and analysis there could be unintended repercussions in areas that had not been anticipated. Before embarking on any changes, we must analyze the potential risks associated with the changes.

Lack of Expertise

It is preferable that testing a database is assigned to the most highly skilled member of the team. Database testing requires proficiency in the query language and practical experience, so should not be undertaken by a team member with a limited understanding of the process.

Conclusion

As databases grow in complexity to be able to handle increasingly detailed data, the demand for testers who possess strong database testing skills and are proficient in the query language.

Author

Ali Imam

Ali is an experienced software tester and has worked with in a variety of areas from e-commerce, healthcare and social networking.