Database security refers to the set of policies, procedures, techniques, and controls used to protect a database from unauthorized access, misuse, modification, disclosure, destruction, and other threats. Since organizational databases store valuable information such as customer details, employee records, financial transactions, business plans, inventory information, and confidential documents, maintaining database security is an essential part of database management. A secure database ensures that authorized users can access the required information while preventing unauthorized users from obtaining or manipulating sensitive data. The primary objective of database security is to maintain the confidentiality, integrity, and availability of organizational data. Confidentiality means that sensitive information should be accessible only to authorized individuals. For example, an employee in the sales department may be permitted to access customer information but may not be authorized to view salary records of employees. Security controls help prevent confidential information from being disclosed to unauthorized users. Another important objective is to maintain data integrity. Data integrity means that information stored in the database should remain accurate, consistent, and reliable. Unauthorized modification, accidental changes, or malicious attacks can damage the quality of database information. Database security mechanisms ensure that only authorized users can insert, update, or delete records and that changes follow established rules. Availability is also an important objective of database security. Authorized users should be able to access data whenever it is required for legitimate business activities. Security measures should therefore protect databases against threats such as malware, denial-of-service attacks, hardware failures, and accidental deletion. Backup and recovery mechanisms play an important role in ensuring continued availability of information. Database security also aims to prevent unauthorized access. Organizations usually have many users with different responsibilities and access requirements. Security controls ensure that users receive only the permissions necessary for their jobs. This reduces the possibility of misuse and limits the damage that can occur if an account is compromised. Accountability is another objective of database security. Database systems should be capable of identifying who accessed or modified particular information. Maintaining records of user activities helps organizations investigate suspicious activities and determine responsibility for unauthorized actions. Audit trails and database logs are commonly used for this purpose. Database security also seeks to protect organizational databases against internal and external threats. Internal threats may arise from employees, administrators, contractors, or other authorized users who misuse their privileges. External threats may include hackers, malware, phishing attacks, and other forms of cybercrime. Security mechanisms provide multiple layers of protection against these threats. Four important database security mechanisms used to protect organizational databases are authentication, authorization and access control, encryption, and auditing. Authentication is the process of verifying the identity of a user before allowing access to the database. It answers the question, “Who is the user?” A database system must ensure that the person attempting to