Statistics & Cardinality: Overview
Module: Query Optimization & Performance
Calculate selectivity and cardinality for single and multi-column predicates
Read histogram buckets to understand value distribution and frequency
Diagnose cardinality estimation errors using EXPLAIN ANALYZE
Understand independence assumption and why it fails for correlated columns
Fix estimation errors with extended statistics, filtered indexes, and query hints
Identify when estimation errors compound in multi-table joins
Calculate selectivity and cardinality for single and multi-column predicates
Read histogram buckets to understand value distribution and frequency
Diagnose cardinality estimation errors using EXPLAIN ANALYZE
Understand independence assumption and why it fails for correlated columns
Fix estimation errors with extended statistics, filtered indexes, and query hints
Identify when estimation errors compound in multi-table joins