SQL Foundations #7: CTEs and Subqueries (And When Each Wins)

Day 7 of SQL Foundations Reframed. Today: the three subquery flavors (scalar, in-list, correlated), CTEs and the multi-step pipeline pattern, the readability argument, the performance question, and a brief tour of recursive CTEs. Same logic, two forms, very different cognitive cost. — THE FULL SERIES — #1 What SQL Actually Is #2 Reading a Query Without Running It #3 SELECT, WHERE, and the Order That Surprises You #4 Joins, Revisited #5 GROUP BY and the Grain Question #6 Window Functions Without the Fear #7 CTEs and Subqueries (And When Each Wins) (you are here) #8 NULL Logic and the Trap That Catches Everyone #9 Reading EXPLAIN (Performance Intuition) #10 Validation in SQL (Capstone) Playlist:    • SQL Foundations #1: What SQL Actually Is (...   Dataset (Lagos Logistics CSVs + README): https://drive.google.com/drive/u/2/fo... — ABOUT — Breakfast with Data is a daily one-hour data education program. Python, SQL, Databricks, data governance, and the reasoning skills that make practitioners genuinely good at their work. Hosted by Ola.