SQL Basics
Reading and writing everyday SQL — joins, NULL handling, grouping, and the statements you should be nervous about running without a WHERE.
Twenty questions on everyday SQL: which join keeps which rows, why comparing to
NULL never works, where WHERE ends and HAVING begins, and the statements
worth double-checking before you press enter.
Aimed at students and developers new to databases. You get a score at the end, not a breakdown.
Leaderboard
…
Grading happens on the server, so this part needs a connection.
Taking the quiz needs an account, so the score is yours and can reach the leaderboard. Sign in with GitHub or Google — reading this page does not need it.
Sign in if you want your score on this board.