Statistics & Cardinality: Overview

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