PostgreSQL Extensions

A reference for 42 extensions that expand what PostgreSQL can do — from query monitoring to vector search to distributed sharding.

Query Optimization Monitoring Search & Spatial Data Types & Utilities Procedural Languages Replication & CDC Compliance & Security Scheduling & Maintenance Performance Scaling Foreign Data & Connectivity

Query Optimization

pg_hint_plan

Control query plans with optimizer hints — useful for testing, migrations, and emergencies.

HypoPG

Test hypothetical indexes without creating them.

pg_qualstats

Collect predicate statistics to detect missing indexes.

pg_ivm

Incremental materialized view maintenance via triggers.

Monitoring

pg_stat_statements

Track query execution statistics — the starting point for any performance investigation.

pg_stat_monitor

Enhanced query monitoring with histograms and per-query plans.

auto_explain

Automatically log execution plans for slow queries.

pg_buffercache

Inspect the contents of the shared buffer cache.

pgstattuple

Measure table and index bloat at the tuple level.

pg_stat_kcache

Track OS-level cache and disk I/O statistics per query — reveals what shared buffer stats hide.

pg_wait_sampling

Continuously sample wait events to identify lock contention, I/O waits, and CPU bottlenecks.

Search & Spatial

pgvector

Vector similarity search for embeddings and AI applications.

PostGIS

Geographic objects and spatial queries in PostgreSQL.

pg_trgm

Trigram-based similarity matching and fast LIKE/ILIKE searches.

bloom

Space-efficient bloom filter indexes for queries filtering on many columns simultaneously.

earthdistance

Great-circle distance calculations without PostGIS — lightweight location queries using cube or point types.

Data Types & Utilities

hstore

Key-value pairs in a single column — the pre-JSONB workhorse, still useful for flat metadata and EAV patterns.

ltree

Hierarchical label trees for representing and querying tree-structured data like org charts and categories.

citext

Case-insensitive text type — eliminates the need for lower() calls and functional indexes on text columns.

uuid-ossp

UUID generation functions including v1 (time-based), v4 (random), and v5 (name-based) variants.

pgcrypto

Cryptographic functions for hashing (SHA-256, bcrypt), encryption (AES, 3DES), and random data generation.

tablefunc

Crosstab and pivot table functions — turn rows into columns for reporting queries.

intarray

Fast operators and GiST indexing for integer arrays — intersection, union, and containment queries.

Procedural Languages

PL/Python

Write PostgreSQL functions and triggers in Python — access the full Python ecosystem from inside the database.

PL/V8

JavaScript procedural language for PostgreSQL — run V8-powered functions with JSON handling and ES6+ syntax.

Compliance & Security

pgAudit

Detailed session and object audit logging for compliance requirements.

Performance

pg_prewarm

Load table and index data into the buffer cache on demand or at startup.

pg_store_plans

Store execution plans alongside pg_stat_statements — see not just which queries are slow, but why.

Scaling

Citus

Distributed PostgreSQL — shard tables across multiple nodes.

TimescaleDB

Time-series optimizations with automatic partitioning and continuous aggregates.