MeritKeep

Aggregate functions

COUNT, SUM, AVG, MIN, MAX, and how each one treats NULL.

core~1hWe mark it against a checklist you can read first
The barWhat counts as knowing this

Aggregate a column correctly, knowing which functions skip NULLs

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

03 · What comes next

What it unlocks

Start on SQL & Data Analysis

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