Learning path
Indexing Mastery
Pick the right index for the access pattern — B-tree, composite, partial, covering, GIN, trigram.
backend, DBA · Intermediate · 3 courses · 7 simulations
The path
Courses, then incidents
Work through the courses, then practise the incidents — each step links to its page.
- Course B-tree Indexes and Selectivity →
- Course Covering, Partial and Expression Indexes →
- Course JSONB, Trigram and Why an Index Is Ignored →
- query-performance Missing index on a hot endpoint →
- query-performance Wrong column order in a composite index →
- query-performance Low-selectivity index trap →
- query-performance Missing trigram index for ILIKE search →
- query-performance GIN index misuse on JSONB →
- query-performance Partial index opportunity →
- query-performance N+1 query pattern (missing child-table index) →