0 to Hero SQL — Stage 1: Foundations
The first three lessons: the relational model, SELECT and its clauses, NULL and three-valued logic, and grouping without double counting. PostgreSQL and MySQL both appear.
Twenty questions on the first stage: the relational model and SELECT, NULL and
three-valued logic, and GROUP BY.
Several questions ask you to distinguish PostgreSQL from MySQL, because that is where the material actually bites. If a question feels like a trick, it is probably one of the four defaults the two engines chose differently.
You get a score, not a list of what you missed.
Leaderboard
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