SQL & Relational Data Basics
SQL & Relational Data Basics groups the core ideas a learner needs at the foundations stage. Work through the lessons in order when new to the area, or use them independently as a reference when implementing an analysis.
Learn the mechanism one decision at a time
Work through the lessons in order if the topic is new. If you already know the basics, open the specific leaf lesson that matches the operation, diagnostic or failure mode you need.
1Definition→
2Mechanism→
3Example→
4Diagnostic→
5Decision
Tables, rows, columns and keysTables, rows, columns and keys is a core data-integration operation. In analytics, correctness depends not only on syntax but on the relationship between keys, row cardinality and the grain of each table.
02SELECT, WHERE and ORDER BYSELECT, WHERE and ORDER BY is a practical concept within SQL & Relational Data Basics. It helps turn the broader workflow stage “Foundations” into an explicit analytical decision that can be explained, implemented and checked. The concept should be understood in terms of purpose, mechanism, assumptions, evidence and downstream consequences.
03GROUP BY and aggregationGROUP BY and aggregation is a core data-integration operation. In analytics, correctness depends not only on syntax but on the relationship between keys, row cardinality and the grain of each table.
04JOIN fundamentalsJOIN fundamentals is a core data-integration operation. In analytics, correctness depends not only on syntax but on the relationship between keys, row cardinality and the grain of each table.
05Window functionsWindow functions is a core data-integration operation. In analytics, correctness depends not only on syntax but on the relationship between keys, row cardinality and the grain of each table.
06CTEs and readable analytical SQLCTEs and readable analytical SQL is a core data-integration operation. In analytics, correctness depends not only on syntax but on the relationship between keys, row cardinality and the grain of each table.