Julia conducted a days of learning SQL contest. The start date of the contest was March 01, 2016 and the end date was March 15, 2016. Write a query to print total number of unique hackers who made at ...

The following challenges all revolve around simple SELECT statements that make use of SELECT, FROM, WHERE, and ORDER BY. The WHERE clauses will use and three basic boolean operators as well as some of ...

Consistent SQL practice across varied platforms builds real job-ready confidence. Guided lessons help beginners, while timed challenges sharpen interview performance. Real datasets improve practical ...