Optimizing database performance in a web application involves several best practices. Start by indexing frequently queried columns to speed up data retrieval, but avoid over-indexing, which can slow down write operations. Use appropriate data types and keep fields as small as possible to enhance efficiency.

Normalize your database to eliminate redundancy, but denormalize when necessary for read-heavy operations to reduce joins. Implement caching mechanisms, such as query caching and in-memory data stores like Redis, to reduce database load.

Regularly analyze and optimize slow queries using tools like the SQL EXPLAIN command to identify and rectify performance bottlenecks. Employ connection pooling to manage database connections efficiently and reduce the overhead of establishing connections.

Partition large tables to improve query performance and manageability. Ensure proper use of transactions to maintain data integrity while minimizing lock contention.

Monitor database performance continuously using performance monitoring tools to identify and address issues proactively. Backup your database regularly and keep it secure to prevent data loss and ensure recovery.

Lastly, consider scaling vertically (adding more resources to the existing server) or horizontally (adding more servers) as your application grows, ensuring the architecture can handle increased load.