Must-know foundational SQL concepts

In this section, we will delve into the foundational SQL concepts that form the building blocks of data engineering. Mastering these fundamental concepts is crucial for acing SQL-related interviews and effectively working with databases.

Let’s explore the critical foundational SQL concepts every data engineer should be comfortable with, as follows:

• SQL syntax: SQL syntax is the set of rules governing how SQL statements should be written. As a data engineer, understanding SQL syntax is fundamental because you’ll be writing and reviewing SQL queries regularly. These queries enable you to extract, manipulate, and analyze data stored in relational databases.
• SQL order of operations: The order of operations dictates the sequence in which each of the following operators is executed in a query:
  • FROM and JOIN
  • WHERE
  • GROUP BY
  • HAVING
  • SELECT
  • DISTINCT
  • ORDER BY
  • LIMIT/OFFSET
• Data types: SQL supports a variety of data types, such as INT...