An SQL developer is a specialist programmer who designs, builds, and maintains the databases that store an application's data. Their core responsibilities include designing database structures (schemas), writing queries to retrieve and manipulate data, and optimizing database performance and security.

1. While there is some overlap, an SQL developer is primarily focused on the data itself—designing tables, writing queries, and creating stored procedures. A DBA is typically more focused on the infrastructure—managing the database server, handling backups and recovery, and ensuring uptime and availability. Our team has skills in both areas.

1. As a database grows, poorly written queries can become extremely slow, causing the entire application to feel sluggish or even time out. Query optimization is the process of rewriting queries and creating indexes to ensure that data can be retrieved in milliseconds, even from tables with billions of rows.

A stored procedure is a pre-compiled set of one or more SQL statements that are saved in the database. Instead of an application sending a long, complex query every time, it can simply call the stored procedure. This improves performance, reduces network traffic, and enhances security.

ETL stands for Extract, Transform, and Load. It is a process used in data warehousing to pull data from various sources (Extract), clean and reformat it (Transform), and then save it into a central data warehouse for reporting and analysis (Load). SQL is a core tool used in this process.

There is no single "best" database. The right choice depends on your needs. MySQL is a fantastic open-source choice for web applications. PostgreSQL is also open-source but has more advanced features. Microsoft SQL Server is a powerhouse for enterprise Windows environments, and Oracle is a long-standing leader in large-scale corporate data management. Our experts can help you choose the right one.