What is Database Testing in DBMS?

A database in DBMS is a collection of data containing information that can be maintained and retrieved by the users. In databases, we have tables for storing the data, triggers for data manipulation, functions, and views for data representation and thus, data management in a database becomes a very easy task in DBMS.

We often have to perform some vital checks on a database to test its responsiveness and functionalities, which is termed Database Testing. DB Testing in DBMS is a type of software testing that is used to analyze the schema, tables, triggers, etc. of a database while testing. Database testing includes performing data integrity and data consistency checks, performance checks related to the database, data validity checks, and testing various procedures.

In Database Testing, we may have to create complex queries and test cases to check the responsiveness of the database. DB Testing consists of a layered process having a User Interface (UI) layer, a Business layer, a Data Access layer, and most importantly the database.

DB Testing is also known as Back-End Testing or Data Validation. To perform db testing, the tester must have a thorough knowledge of the database concepts and SQL in DBMS.

Example: Let us consider that we have a software application that maintains the daily-life transaction details for the users and stores everything in the database. If we have to perform DB testing, the following checks should be conducted at regular intervals of time:

• Data should be consistent i.e, it should not be lost when it is loaded into the database.
• Unauthorized users should not have the access to the user information in the database.
• Only the completed transactions should be stored in the database and the rest incomplete transactions should get aborted by the application. To learn more about transaction in DBMS click here.

Why do we Need to use Database Testing in DBMS?

Database Testing in DBMS is an important type of Software Testing that ensures the efficiency, maximum stability, performance, and security of the database. Database Testing in DBMS helps in saving data loss, saving aborted transaction data, and restricting unauthorized users from accessing the database.

Usually, the Graphical User Interface (GUI) i.e, the Front-End part of the application is given the most emphasis by the testing and the development team but however, but it becomes important to validate the information i.e, the database at the Back-End (heart of the application).

Some of the main reasons for the need to perform DB Testing include:

• DB Testing is performed on the Back-End system which increases the robustness (quality and stability) of the data.
• Developers often use views and procedures in DBMS to optimize and ease the complexity of SQL query calls on the database. These stored procedures and views can contain critical tasks like inserting users' confidential details, their sales data, etc. which need to be tested at various levels.
• In a database especially a data warehouse system, where data is centralized from various sources, there is a possibility that harmful or incorrect data is being stored in the system. Therefore, it becomes important to check the database components regularly along with data integrity and data consistency.

What is the Objective of Database Testing in DBMS?

The main purpose and objectives of Database Testing are to ensure that the following aspects are being followed:

• Transactional ACID Properties
• Data Integrity
• Accuracy of Business Rules
• Data Mapping

1. Transactional ACID Properties Atomicity, Consistency, Isolation, and Durability are the ACID Properties in DBMS.

• Atomicity - The term atomicity in DBMS means that either the entire transaction takes place at once or doesn’t happen at all. There is no midway i.e, transactions do not occur partially.
• Consistency - The term consistency specifies that the database remains consistent before and after the transaction. The data should always remain preserved and should always be correct.
• Isolation - The term Isolation means that multiple transactions can take place in DBMS without impacting one another and changing the database state.
• Durability - This property ensures that once the transaction has completed its execution, the updates and modifications to the database are stored in and written to disk and they persist even if a system failure occurs.

2. Data Mapping In Data Mapping, we check and analyze whether Front-End entry fields are mapped constantly with the equivalent fields in the database table or not. When a specific operation is performed at the Front-End of an application, CRUD (Create, Retrieve, Update and Delete) activity operations are implemented at the Back-End.

The main purpose of Data Mapping is to focus on verifying user data that is being stored or retrieved from the database at the Back-End of the application.

3. Data Integrity Data Integrity ensures that whenever we change or update any data value in the database, it should get reflected on all the forms and screens. This should not be the case that the updated value is being shown on one screen and the older value on the other.

4. Accuracy of the Business Rules Complex databases lead to complex components and complex queries and hence, testers should always use appropriate SQL commands to verify complex objects like relational constraints, triggers, procedures, etc. Database testing, therefore, ensures the accuracy of the business rules.

What are the Database Components / Testing Attributes?

The DB testing attributes or the database components in DBMS are as follows:

• Database schema
• Transactions
• Stored procedures
• Field constraints
• Triggers

1. Database Schema A database schema in DBMS is used to describe the structure and the working of data in a database. It specifies how the data is planned to be stored and functional in the database.

2. Transactions Accessing and Retrieving the data from the database in DBMS is termed a transaction. ACID properties must be followed while executing a transaction in DBMS.

3. Stored Procedures It is the collection of the statements or functions governing the transactions in a database. The stored procedure system is used for multiple applications where data is kept in RDBMS (Relational DBMS).

4. Field Constraints Field constraints are another database testing components where the entire database system works on the default value, exclusive value, primary key, foreign key, etc. In this way, we can verify the results and the outcomes retrieved from SQL query commands.

5. Triggers When a certain event occurs in a table in the database, triggers are auto-instructed to be executed. Trigger components are implemented independently on an entire table to record outputs.

What is Database Testing Process?

There are a total of five processes involved in Database Testing:

• Testing Environment Setup Database Testing starts by setting up the testing environment for carrying out a good quality testing process.
• Testing scenario generation Now after setting up the test environment, test cases are being created. Test cases involve different inputs & different transactions related to the database.
• Execution The execution phase is the core phase of the testing process and in this phase, we try to execute the already designed test cases (including edge cases too).
• Analysis After executing all the test cases, it's time to analyze all the outputs obtained, matching them with the expected results. It also signifies whether the testing process has been carried out properly or not.
• Log Defects Log defects signify report submission and this is the last phase in database testing. Basically, the tester informs the developer about the issues/defects found in the database for the software application.

What are the Types of Database Testing?

DB testing in DBMS is broadly classified into three different types:

• Structural Testing
• Functional Testing
• Non-Functional Testing

1. Structural Database Testing in DBMS Structural DB Testing involves testing different database components which are not exposed to the end users. It deals with table testing, schema testing, checking triggers, views testing, etc. This type of testing is usually conducted by data administrators who have good knowledge of SQL concepts. Structural database testing is mainly performed to validate the database.

Structural DB Testing is further classified into various types that we have discussed below: Schema / Mapping Testing It involves validating the data entry field components of the Front-End application after mapping with the database components. This testing is important in cases where the end-user application components are not rightly mapped with the database objects.

Stored Procedures and Views Testing While testing for stored procedures and views, the tester ensures:

• If the development team has checked and acknowledged all the conditions in the procedures.
• If the triggers that are required to be executed, are enabled as expected or not.
• If some of the stored procedures in the database are left unused/unchecked.
• If all error handling mechanisms are being followed.

Trigger Testing While testing for triggers, the tester ensures:

• Whether all the executed triggers meet the required conditions or not.
• Whether coding conventions are being followed while coding triggers.
• Responsiveness of the triggers after their execution (whether triggers update the data correctly as per requirements after their execution).

Database Server Check In testing for the Database Server, we verify:

• If the database system can handle a large number of business transactions as per the requirements.
• If only authorized users have access to the database system.

2. Functional Database Testing in DBMS Functional DB Testing is the most important type of database testing in DBMS which is used to authorize database functional requirements. The main purpose of Functional Testing is to test whether the user's transactions or other activities are connected to the database as expected or not. Functional Testing in DBMS is further classified as Black Box Testing and White Box Testing.

Black Box Testing In Black Box Testing, testers are not concerned about the internal functioning or the code of the core application. This testing involves verifying the integrated database system for checking the functionalities. Test cases designed for this testing are simple & easy to execute.

White Box Testing In White Box Testing, we are only concerned about the internal structure of the database and thus, the tester must be well-versed in the code and internal functioning of the application. This testing involves testing the database triggers, logical views, etc. This testing helps in validating database schema, its tables, and the overall model.

3. Non-Functional Database Testing in DBMS Non-Functional Database Testing in DBMS involves checking for minimum system requirements to meet the business specifications and for performance optimization of the database. It involves Load Testing and Stress Testing.

Load Testing Load Testing in DBMS is used to check the performance impact (load) of the running transactions on the database. In Load Testing, the tester checks:

• The response time for executing multiple transactions parallelly for multiple remotely located end users.
• Time is taken by the database to retrieve specific records as per the requirements.
• Examples of Load Testing in real-life situations:
  1. Downloading a series of large-size files from the internet.
  2. Running more than one application on a computer/server at the same time.

Stress Testing As the name suggests, Stress Testing in DBMS is conducted to identify the system breakpoint. In this type of testing, the application is loaded in such a way that the system will definitely fail at one point in time. This point of failure for a system is known as the database system breakpoint. Some of the stress testing tools are LoadRunner and WinRunner.

How to Perform Database Testing Manually and With the Help of Automation Tool?

We have discussed a lot about Database Testing till now about why we need database testing, and what are the objectives of database testing but now, the main question arises, how to perform database testing in DBMS ? In DBMS, Database Testing can be done either manually or with the help of available automation tools.

1. Database Testing (Manually) To test databases manually, we need to follow the below-mentioned steps:

• Open SQL server in the local system. (Install if not already installed)
• Now, open the query analyzer to write query commands to retrieve the data.
• Once the specified data has been retrieved, now the detailed data can be compared with the expected results.
• One can also update/delete the data to check the responsiveness & performance of the software application.
• To run the test cases, we have to follow some more procedural steps:
  1. Set up the test environment required for testing software applications.
  2. Execute the test cases (Run test cases along with some edge cases)
  3. When test cases are executed successfully without any error, note down the specified test case results.
  4. If results meet the expected output, then the test cases are considered as passes.

2. Database Testing (With the help of Automation Tools) Automated Testing is used to decrease the repetitive manual work and helps testers and developers to focus on other critical features of the application. Some of the situations where automated testing can be helpful for the testers are discussed below:

• Modifications in Database schema Whenever schema is modified in DBMS, we need proper database testing to ensure everything is in place. This process is real-time and time-consuming. If we try to do it manually, we won't be able to cover all the scenarios considering the large size of the database. Therefore, automation is required for this scenario.
• Monitoring Data Integrity issues There are possibilities where a set of data gets corrupted in recovery backup or any other activity because of any issue or human error. If we try using automation for monitoring processes, it gets easier to fix the issues within the database.

What are the Different Challenges We may Face During Database Testing?

While performing DB testing, we may encounter some of the challenges discussed below:

• To test a database, it is fundamental to have good knowledge of DBMS and SQL concepts and hands-on database management tools.
• Testing scope is too large. When the database size is too large, it becomes difficult to find out which objects need to be tested and which ones to be left out.

Solution - Testers must have a clear understanding of what they need to test or otherwise, they may waste a lot of time testing uncritical components of the database. A scaled-down database is always a good solution because it is always as close as possible to the production data set.

• As database structure can be complex and too large to handle, testers may execute the same tests repeatedly. They must have a clear test plan and while executing, they must check the progress at regular intervals.
• While testing a database, it might happen that that database structure gets modified and this is one of the most common challenges faced by the testing team. One must be aware of the changes made to the database while testing. Testers need to analyze and modify the test cases in accordance with the changes made in the database.
• New test data have to be designed again only after cleaning up the old test-case data.
• The setup of the database testing procedure can be costly and time-consuming.

Solution - We know that the software product quality depends on the cost but there should always be a balance maintained between quality assurance and the overall cost-effectiveness of the project.

• Unwanted data modification is also another common challenge while maintaining a database system and during its testing.

Solution - The best solution is access control and data modification control should be given to selective people only.

What are the Misconceptions Related to Database Testing?

While we perform DB testing in DBMS, we may encounter some myths or misconceptions about database testing. Some of the misconceptions related to Database Testing in DBMS are as follows:

• Does DB testing requires expertise and knowledge? And also, is it a monotonous job to test the databases?

Reality: Effective DB testing provides long-term stability to the whole application and hence, it is always important to invest proper time and knowledge in testing the databases.

• Does Database Testing slows down the overall development process?

Reality: Ample amount of time invested in database testing helps in improving the quality and stability of the database and the overall application.

• Is Database testing a very costly process to conduct?

Reality: It is a long-term investment if we talk about expenditure on database testing that results in the optimization of the application.

• Does Database Testing adds an extra work bottleneck?

Reality: DB Testing adds value to our work and helps find out hidden issues within the database and thus, helps in improving the overall application.

Read More:

• Components of DBMS.
• DBMS Applications.
• Databases Types.