Overview: Consistent SQL practice across varied platforms builds real job-ready confidence.Guided lessons help beginners, while timed challenges sharpen intervi ...

Normalized data giving you problems? Learn how to use the SQL subselect statement and handle your database like a pro! Do you ever find yourself juggling queries to get the information you need?

Thanks to the technology behind ChatGPT, it’s become surprisingly simple to query a data set in plain English. As with most generative AI, results from OpenAI’s API are still imperfect, which means ...

Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

Much of the world's data lives in databases. SQL (or Structured Query Language) is a powerful programming language that is used for communicating with and extracting various data types from databases.

A common SQL habit is to use SELECT * on a query, because it’s tedious to list all the columns you need. Plus, sometimes those columns may change over time, so why not just do things the easy way? But ...