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VIDEO / PostgreSQL / Databases

PostgreSQL Indexes Explained

A visual mental model for indexes, scans, selectivity, and query planning.

PostgreSQLDatabases
DURATION
15:42
PUBLISHED
Aug 15, 2026
CHAPTERS
4
TOPICS
PostgreSQL · Databases

VIDEO / CHAPTERS

Inside this explanation

  1. 00:00Table scans
  2. 03:18Inside a B-tree
  3. 08:06Selectivity and cost
  4. 12:14Reading EXPLAIN
WATCH ON YOUTUBE
01

The picture

We build an index from the leaf pages upward, then follow the planner as it compares index and sequential access.

  • Ordered keys
  • Heap lookups
  • Cost estimates
02

Apply it

The final chapter turns the mental model into a repeatable query-tuning workflow.