Read-only practice
YOUR FIRST QUERY STARTS HERE
Make data
make sense.
Learn SQL by asking real questions of a small school library. Try a query, see what comes back, and follow the clues.
Explore a first lesson ↓✳
✳
membersmember_id name1 Avery2 Sam
loansmember_id book_id1 1012 104
booksbook_id title101 The Wild Robot104 The Hobbit
THREE TABLES, ONE STORY ↗
01 / LEARN BY DOING
Start with a question.
A small library dataset · 3 short lessons
SQL EDITOR / school_library
POSTGRESQL · READ ONLYASKFind the newest books in the library.
⌘ ↵ to run
RESULTS / Run a query to see results
✳Your results will show up here.Start with the example, then make it your own.
02 / FOLLOW THE DATA
Know what you’re querying.
Three related tables. Find the keys, follow a relationship, and see how the pieces fit.
Connecting to the teaching database…
⌑ Keys ending in
_id connect records across tables.✳
A GOOD PLACE TO BEGIN
Start with SELECT and FROM. Add one question at a time. The database is read-only, so you can explore freely.