Software Engineer working on a project to develop skills

SQL developers play a critical role in designing and optimizing databases to ensure efficient data storage, retrieval, and management. To excel in this role, they require a combination of technical skills, knowledge, and practical experience.

Let’s break down the most essential SQL skills, along with the training and knowledge necessary to truly succeed in this role!

What does an SQL developer do?

Relational SQL databases organize data into rows and columns. If you’re brand new to the concept of relational databases and what it takes to effectively manage them, you can learn Codd’s Twelve Rules that granularly define a relational database management system. 

The SQL language allows you to modify a database’s index structures, retrieve information, and generate new tables. Once you have a foundation of SQL knowledge, you can add a universe of associated skills and tools, including commercial SQL IDEs that help you complete certain tasks (Squirrel!). SQL developers understand SQL and relational databases, and they help companies build and maintain those databases.

What skills does an SQL developer need?

As a baseline, SQL developers must be proficient in the following:

  • SQL: Programming language for relational databases.
  • Microsoft SQL Server: Microsoft’s database management system.
  • Azure SQL Database: Microsoft’s cloud-based database management system.
  • MySQL: An open-source database management system.
  • PostgreSQL: Another popular open-source database management system.
  • Excel: Spreadsheets.
  • PivotTables: An Excel feature that allows you to effectively summarize and analyze data.
  • Other programming languages: Java, Python, and other programming languages can become important in database creation and management.

In addition, SQL developers must have a solid grasp of “soft skills” such as communication and empathy, as they’ll spend a lot of time communicating project details and results to a variety of team members and stakeholders, including senior management.

SQL developers must also internalize how to best secure data, especially in industries such as healthcare that are bound tightly by privacy regulations. “Ensuring the integrity and security of data in databases is important to protect sensitive information and comply with data privacy regulations,” explains Trish Orzoco, recruiting manager for LaSalle Networks. “SQL developers need a range of skills and practices to achieve this.”

This means SQL developers must also know:

  • Authentication
  • Encryption
  • Auditing and monitoring
  • Incident response
  • Data backup and recovery

Orzoco adds that familiarity with database schema, including tables, indexes, and relationships, is crucial for crafting optimized queries. “The ability to analyze query execution plans generated by the database engine is crucial for identifying bottlenecks and areas for optimization.”

How can an SQL developer get training?

Given the ubiquity and popularity of SQL, there are lots of training options available. Many two- and four-year programs in computer science and other tech disciplines will cover SQL. In addition, there are many online training courses in everything SQL-related, including:

In addition to online courses, there are also textbooks on SQL, and practice via projects and real-world scenarios.

Beyond the basics: Mastery of database design principles

Sunil Kalra, associate director of data engineering at LatentView Analytics, points out that SQL developers should have a strong understanding of database design principles, including normalization, indexing, and data modeling.

“This involves structuring the database schema efficiently to support the required functionality and performance,” he says. “In today's era of public cloud computing, inefficient database designs can result in increased costs.”

Despite the rise of A.I.-driven technologies, SQL query optimization remains crucial despite advancements in automated optimization by database engines. “Therefore, having a solid understanding of query execution plans, optimizing query performance through indexing, and employing appropriate join techniques is highly valuable for SQL developers,” Karla says.

SQL developers should also have experience in identifying and resolving performance bottlenecks in databases. “This involves analyzing query performance, optimizing database configurations, and implementing caching strategies,” he explains. “Inefficient queries cost lot of money.”

What regulations do SQL developers need to know?

In today's digital landscape, ensuring data security and privacy is of utmost importance, which means SQL developers must be well-versed in the security and compliance requirements relevant to their organization. This includes understanding regulations such as GDPR and the California Information Protection Act.

To meet these requirements, professionals need to implement appropriate security measures. “This may involve techniques such as data masking and access control to protect sensitive information,” Karla says. “Data masking involves replacing real data with fictional or anonymized data during development and testing, minimizing the risk of unauthorized access.”

From Karla's perspective, continual learning and awareness of emerging trends are essential to effectively address security challenges and ensure compliance with relevant laws. By understanding their specific security and compliance requirements and implementing the necessary measures, SQL developers can safeguard data integrity and help the organization protect against potential losses and breaches.

Mark Chaffey, CEO and co-founder of Hackajob, suggests data security and privacy are ensured through a multi-layered approach. “SQL developers should be familiar with encryption techniques, data masking, and access control mechanisms to secure data,” he says. “Understanding SQL injection attacks and how to prevent them is also vital.”

He also agrees compliance with regulations such as GDPR may be required depending on the industry. “Training in cybersecurity specifically tailored to databases can be invaluable, and professionals can often find this training through certified courses, or through their employer,” he adds.

Don’t sleep on soft skills

Chaffey notes communication and collaboration are crucial for SQL developers. “They need the ability to translate complex technical requirements into layman's terms and vice versa,” he says. “Familiarity with project management tools like Jira and collaborative platforms like Slack can facilitate this.”

SQL developers should also be comfortable with version control systems like Git to effectively collaborate on code. “Soft skills such as active listening and empathy are important to understand the needs of other team members like software engineers or data analysts,” Chaffey explains. “Modern data teams have moved to managing data as a product—applying the same principles to projects in data as we do to projects in software.”

This contrasts to the old method of siloed, command and control style work, and instead is much more collaborative and user-focused. “By seeing data as a product designed for end-user consumption, instead of a mess of information that needs to be stored and organized, we can focus the data team on producing real, tangible business results,” he says.

When working with software engineers or data analysts, SQL developers need to be proactive in understanding their needs and not make assumptions. “While the engineers and analysts may have a clear understanding of the data they require, it is the developer's responsibility to consider factors such as scalability and performance in the SQL queries,” Karla adds.

This requires asking relevant questions to ensure that the queries are optimized and aligned with the team's requirements—yet another reason why SQL developers need effective communication skills.

Chaffey agrees with Karla that continuous learning is a necessity in the fast-paced world of data engineering, with frequent introduction of new tools and patterns, even if SQL development itself hasn’t evolved overmuch.

SQL developer professionals can stay up-to-date by enrolling in online courses, following SQL-related blogs and forums, (for example, Stack Overflow), and participating in open-source projects.