MeritKeep

Semi and anti joins

EXISTS, NOT EXISTS, IN, NOT IN and the NULL trap in NOT IN; EXCEPT and INTERSECT.

advanced~2hWe mark it against a checklist you can read first
The barWhat counts as knowing this

Find rows that do or do not have a match without changing the result grain

That sentence is the bar. It only counts once your work shows you can do it. Reading about it does not.
Prove itA check for this one skill

Up to 2 questions on this skill alone, marked against the bar beside this. It stops as soon as the answer is clear. No account, and your answers are not kept.

01 · Prerequisites

You'll need these first

02 · Also helpful

Helpful, but not required

Start on SQL & Data Analysis

Every skill above, ordered by what depends on what, with the projects above that as the evidence you actually did it. We work out where you already are first, so the path skips what you can do.

About three minutes to set up. Nothing is marked until you hand something in.Start this path
Part of SQL & Data Analysis.

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