A Database Engineer is responsible for designing, implementing, and maintaining databases that store and manage data for applications or systems. They work with database management systems (DBMS) like MySQL, PostgreSQL, or Oracle to create optimized, scalable, and secure database structures. Their tasks include writing and optimizing complex queries, ensuring data integrity, performing regular backups, and troubleshooting database issues. Database engineers also focus on performance tuning, data security, and ensuring high availability, often working closely with software developers and system administrators to integrate the database seamlessly into the overall system architecture.