SQL
from Scratch
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Chapters
The course
SQL from Scratch
38 lessons across eleven chapters. Each one starts with a question Harry can’t answer yet.
00
Before SQL
What data, tables, rows, and databases actually are.
1 lesson
01
Asking Questions
Looking inside a table for the first time.
1 lesson
02
Filtering
Deciding which rows are allowed to stay, then putting them in order.
2 lessons
03
Aggregation
Making the database do the math instead of doing it yourself.
4 lessons
04
Joins
The database is split across tables, and that's on purpose.
3 lessons
05
Subqueries
Asking questions inside questions.
2 lessons
06
CTEs
Making complex questions readable again.
1 lesson
07
Window Functions
Calculating across related rows without collapsing them.
5 lessons
08
Analytics
Thinking like a data analyst, one business question at a time.
7 lessons
09
Problem Solving
Reusable patterns for the questions that show up again and again.
8 lessons
10
Projects
No prescribed concepts. Just business questions and a messy database.
4 lessons