PostgreSQL Maintenance Cheat Sheet

PostgreSQL Maintenance Cheat Sheet

PostgreSQL Maintenance Commands Cheat Sheet

VACUUM

Frees space from dead tuples and makes pages reusable without locking out writers. 

-- vacuum a single table
VACUUM store.customers;

-- vacuum all tables in the current database
VACUUM;

VACUUM FULL

Fully rewrites a table to compact it and return space to the OS (locks the table). 

-- reclaim disk space on a large table
VACUUM FULL store.orders;

ANALYZE

Collects statistics on column distributions for the planner to choose optimal plans. 

-- update stats for specific tables
ANALYZE store.emp;
ANALYZE store.dept;

-- analyze entire database
ANALYZE;

REINDEX

Rebuilds an index to remove fragmentation and bloat. 

-- rebuild a single index
REINDEX INDEX store.ix_orderlines_orderid;

-- rebuild all indexes on a table
REINDEX TABLE store.orderlines;

Best Practices

  • Enable autovacuum to run VACUUM & ANALYZE automatically.
  • Use VACUUM FULL sparingly during low-traffic windows.
  • Monitor bloat via pg_stat_user_tables and pg_stat_user_indexes.
  • Schedule REINDEX after bulk loads or heavy DELETE cycles.

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