7 min read

According to Robert Half Technology’s 2019 IT salary report, ‘Database programmer’ is one of the 13 most in-demand tech jobs for 2019. For an entry-level programmer, the average salary is $98,250 which goes up to $167,750 for a seasoned expert. A typical database programmer is responsible for designing, developing, testing, deploying, and maintaining databases. In this article, we will list down the top critical tech skills essential to database programmers.

#1 Ability to perform Data Modelling

The first step is to learn to model the data. In Data modeling, you create a conceptual model of how data items relate to each other.

In order to efficiently plan a database design, you should know the organization you are designing the database from. This is because Data models describe real-world entities such as ‘customer’, ‘service’, ‘products’, and the relation between these entities. Data models provide an abstraction for the relations in the database. They aid programmers in modeling business requirements and in translating business requirements into relations. They are also used for exchanging information between the developers and business owners.

During the design phase, the database developer should pay great attention to the underlying design principles, run a benchmark stack to ensure performance, and validate user requirements. They should also avoid pitfalls such as data redundancy, null saturation, and tight coupling.


#2 Know a database programming language, preferably SQL

Database programmers need to design, write and modify programs to improve their databases. SQL is one of the top languages that are used to manipulate the data in a database and to query the database. It’s also used to define and change the structure of the data—in other words, to implement the data model. Therefore it is essential that you learn SQL.

In general, SQL has three parts:

  • Data Definition Language (DDL): used to create and manage the structure of the data
  • Data Manipulation Language (DML): used to manage the data itself
  • Data Control Language (DCL): controls access to the data

Considering, data is constantly inserted into the database, changed, or retrieved DML is used more often in day-to-day operations than the DDL, so you should have a strong grasp on DML. If you plan to grow in a database architect role in the near future, then having a good grasp of DDL will go a long way.

Another reason why you should learn SQL is that almost every modern relational database supports SQL. Although different databases might support different features and implement their own dialect of SQL, the basics of the language remain the same. If you know SQL, you can quickly adapt to MySQL, for example.

At present, there are a number of categories of database models predominantly, relational, object-relational, and NoSQL databases. All of these are meant for different purposes. Relational databases often adhere to SQL. Object-relational databases (ORDs) are also similar to relational databases. NoSQL, which stands for “not only SQL,” is an alternative to traditional relational databases useful for working with large sets of distributed data. They provide benefits such as availability, schema-free, and horizontal scaling, but also have limitations such as performance, data retrieval constraints, and learning time.

For beginners, it is advisable to first start with experimenting on relational databases learning SQL, gradually transitioning to NoSQL DBMS.

#3 Know how to Extract, Transform, Load various data types and sources

A database programmer should have a good working knowledge of ETL (Extract, Transform Load) programming. ETL developers basically extract data from different databases, transform it and then load the data into the Data Warehouse system. A Data Warehouse provides a common data repository that is essential for business needs. A database programmer should know how to tune existing packages, tables, and queries for faster ETL processing. They should conduct unit tests before applying any change to the existing ETL process. Since ETL takes data from different data sources (SQL Server, CSV, and flat files), a database developer should have knowledge on how to deal with different data sources.

#4 Design and test Database plans

Database programmers o perform regular tests to identify ways to solve database usage concerns and malfunctions. As databases are usually found at the lowest level of the software architecture, testing is done in an extremely cautious fashion. This is because changes in the database schema affect many other software components. A database developer should make sure that when changing the database structure, they do not break existing applications and that they are using the new structures properly.

You should be proficient in Unit testing your database. Unit tests are typically used to check if small units of code are functioning properly. For databases, unit testing can be difficult. So the easiest way to do all of that is by writing the tests as SQL scripts.
You should also know about System Integration Testing which is done on the complete system after the hardware and software modules of that system have been integrated. SIT validates the behavior of the system and ensures that modules in the system are functioning suitably.

#5 Secure your Database

Data protection and security are essential for the continuity of business. Databases often store sensitive data, such as user information, email addresses, geographical addresses, and payment information. A robust security system to protect your database against any data breach is therefore necessary.

While a database architect is responsible for designing and implementing secure design options, a database admin must ensure that the right security and privacy policies are in place and are being observed. However, this does not absolve database programmers from adopting secure coding practices.

Database programmers need to ensure that data integrity is maintained over time and is secure from unauthorized changes or theft. They need to especially be careful about Table Permissions i.e who can read and write to what tables. You should be aware of who is allowed to perform the 4 basic operations of INSERT, UPDATE, DELETE and SELECT against which tables.

Database programmers should also adopt authentication best practices depending on the infrastructure setup, the application’s nature, the user’s characteristics, and data sensitivity. If the database server is accessed from the outside world, it is beneficial to encrypt sessions using SSL certificates to avoid packet sniffing. Also, you should secure database servers that trust all localhost connections, as anyone who accesses the localhost can access the database server.

#6 Optimize your database performance

A database programmer should also be aware of how to optimize their database performance to achieve the best results. At the basic level, they should know how to rewrite SQL queries and maintain indexes. Other aspects of optimizing database performance, include hardware configuration, network settings, and database configuration.

Generally speaking, tuning database performance requires knowledge about the system’s nature. Once the database server is configured you should calculate the number of transactions per second (TPS) for the database server setup. Once the system is up and running, and you should set up a monitoring system or log analysis, which periodically finds slow queries, the most time-consuming queries, etc.

#7 Develop your soft skills

Apart from the above technical skills, a database programmer needs to be comfortable communicating with developers, testers and project managers while working on any software project. A keen eye for detail and critical thinking can often spot malfunctions and errors that may otherwise be overlooked.

A database programmer should be able to quickly fix issues within the database and streamline the code. They should also possess quick-thinking to prioritize tasks and meet deadlines effectively. Often database programmers would be required to work on documentation and technical user guides so strong writing and technical skills are a must.

Get started

If you want to get started with becoming a Database programmer, Packt has a range of products.

Here are some of the best:

PostgreSQL 11 Administration Cookbook

Learning PostgreSQL 11 – Third Edition

PostgreSQL 11 in 7 days [ Video ]

Using MySQL Databases With Python [ Video ]

Basic Relational Database Design [ Video ]

Read Next

How to learn data science: from data mining to machine learning

How to ace a data science interview

5 barriers to learning and technology training for small software development teams

Content Marketing Editor at Packt Hub. I blog about new and upcoming tech trends ranging from Data science, Web development, Programming, Cloud & Networking, IoT, Security and Game development.