PostgreSQL Learn Center
Understand the signal before changing the database.
Source-backed explanations, safe inspection queries, and interpretation guardrails for PostgreSQL operators. Every guide separates what a measurement shows from what it cannot prove.
Published topics
The center grows by topic. Overlapping size articles keep their established guide URLs, while new subjects live directly in the Learn Center.
Size and storage
Understand the bytes PostgreSQL reports and what those measurements include.
How to check PostgreSQL database size
Measure database and relation storage, then interpret what each size function includes.
Read guideWhy your PostgreSQL database keeps growing
Separate logical data and index growth from reusable space, WAL retention, and provider disk measurements.
Read guidePostgreSQL WAL basics
Distinguish WAL generation from retention and inspect cumulative totals and replication slots safely.
Read guide
Queries and workload
Interpret query activity, latency, and workload evidence.
Tables and indexes
Inspect relation footprint and evaluate table and index signals safely.
Connections
Understand sessions, limits, pooling, and connection pressure.
How to read pg_stat_activity
Inspect current session states and waits without treating a single activity snapshot as a trend.
Read guidePostgreSQL connection pooling
Compare direct, session, and transaction modes and interpret database-facing connection counts safely.
Read guidePostgreSQL idle-in-transaction sessions
Inspect transaction age and ownership clues before terminating sessions or changing timeouts.
Read guide
Maintenance
Learn how vacuum, analyze, and related operations affect a database.
Monitoring
Turn PostgreSQL observations into useful, appropriately qualified trends.
Ready to inspect your own result?
Use the free tools for a bounded snapshot, or connect a database to let DatabaseMeter collect supported statistics over time.