This course outlines the basics of the SQL language – unlike other courses, which contain a lot of syntax elements that, in fact, are rarely used in practice – here you will gain exactly those skills that are often used in practice.

This will allow you to start working immediately without wasting extra time. The SQL language seems simple – and it really is. However, each case has its own subtleties. And these subtleties are outlined in this course – working with NULL values, duplicate rows and loss of rows when joining tables, and many others.

The course includes practical assignments. So you will not just watch the lectures, but also write SQL queries yourself. Also, after each exercise we analyze the solutions to these tasks. This is a compact course to save your time. All material is presented concisely. The structure of the course is designed in such a way that you get a holistic picture of developing SQL queries. You will learn SQL applicable to many databases.

The exercises are performed in PostgreSQL. However, we do not cover features specific to PostgreSQL. Therefore, the knowledge gained is applicable to other databases: PostgreSQL, Oracle, Microsoft SQL Server, MySQL, Teradata, Amazon Redshift, Google BigQuery and many others.

The basic SQL constructs are the same everywhere. The focus is on writing SELECT queries to read data. It often happens that tables have already been created and data has been loaded into them. And the task is to write a sample of data from these tables correctly and without errors.